Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.0 updates its dependency 'OpenSSL' to v3.1.1 to include a security fix.
https://github.com/pyca/cryptography/commit/8708245ccdeaff21d65eea68a4f8d2a7c5949a22

Cryptography 41.0.3  updates its bundled OpenSSL version to include a fix for CVE-2023-2975: AES-SIV implementation ignores empty associated data entries.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230714.txt

Affected versions of the cryptography package are vulnerable to Improper Input Validation due to missing prime-order subgroup validation for SECT elliptic-curve points. The public_key_from_numbers, EllipticCurvePublicNumbers.public_key(), load_der_public_key(), and load_pem_public_key() entry points accept attacker-supplied public keys without verifying that the provided point lies in the expected prime-order subgroup, enabling small-subgroup points to pass as valid.

Cryptography 41.0.4 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.3, that includes a security fix.
https://github.com/pyca/cryptography/commit/fc11bce6930e591ce26a2317b31b9ce2b3e25512

Cryptography 39.0.1 includes a fix for CVE-2022-3996, a DoS vulnerability affecting openssl.
https://github.com/pyca/cryptography/issues/7940

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/b22271cf3c3dd8dc8978f8f4b00b5c7060b6538d
https://www.openssl.org/news/secadv/20230731.txt

The `cryptography` library has updated its BoringSSL and OpenSSL dependencies in CI due to a security concern. Specifically, the issue involves the functions `EVP_PKEY_param_check()` and `EVP_PKEY_public_check()`, which are used to check DSA public keys or parameters. These functions can experience significant delays when processing excessively long DSA keys or parameters, potentially leading to a Denial of Service (DoS) if the input is from an untrusted source. The vulnerability arises because the key and parameter check functions do not limit the modulus size during checks, despite OpenSSL not allowing public keys with a modulus over 10,000 bits for signature verification. This issue affects applications that directly call these functions and the OpenSSL `pkey` and `pkeyparam` command-line applications with the `-check` option. The OpenSSL SSL/TLS implementation is not impacted, but the OpenSSL 3.0 and 3.1 FIPS providers are affected by this vulnerability.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography package before 41.0.2 for Python mishandles SSH certificates that have critical options.

Cryptography 39.0.1 includes a fix for CVE-2023-23931: In affected versions 'Cipher.update_into' would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as 'bytes') to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This issue has been present since 'update_into' was originally introduced in cryptography 1.8.

Cryptography 3.3 no longer allows loading of finite field Diffie-Hellman parameters of less than 512 bits in length. This change is to conform with an upcoming OpenSSL release that no longer supports smaller sizes. These keys were already wildly insecure and should not have been used in any application outside of testing.
https://github.com/pyca/cryptography/pull/5592

Cryptography 3.2 and prior are vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

Cryptography starting from version 42.0.0 updates its CI configurations to use newer versions of BoringSSL or OpenSSL as a countermeasure to CVE-2023-5678. This vulnerability, affecting the package, could cause Denial of Service through specific DH key generation and verification functions when given overly long parameters.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

The cryptography library has updated its OpenSSL dependency in CI due to security concerns. This vulnerability arises when processing maliciously formatted PKCS12 files, which can cause OpenSSL to crash, leading to a potential Denial of Service (DoS) attack. PKCS12 files, often containing certificates and keys, may come from untrusted sources. The PKCS12 specification allows certain fields to be NULL, but OpenSSL does not correctly handle these cases, resulting in a NULL pointer dereference and subsequent crash. Applications using OpenSSL APIs, such as PKCS12_parse(), PKCS12_unpack_p7data(), PKCS12_unpack_p7encdata(), PKCS12_unpack_authsafes(), and PKCS12_newpass(), are vulnerable if they process PKCS12 files from untrusted sources. Although a similar issue in SMIME_write_PKCS7() was fixed, it is not considered significant for security as it pertains to data writing. This issue does not affect the FIPS modules in versions 3.2, 3.1, and 3.0.

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 3.3.2 includes a fix for CVE-2020-36242: certain sequences of update calls to symmetrically encrypt multi-GB values could result in an integer overflow and buffer overflow, as demonstrated by the Fernet class.

Affected versions of Cryptography may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.

Cryptography 41.0.3 updates its bundled OpenSSL version to include a fix for a Denial of Service vulnerability.
https://github.com/pyca/cryptography/commit/bfa4d95f0f356f2d535efd5c775e0fb3efe90ef2
https://www.openssl.org/news/secadv/20230719.txt

Cryptography version 42.0.5 introduces a limit on the number of name constraint checks during X.509 path validation to prevent denial of service attacks.
https://github.com/pyca/cryptography/commit/4be53bf20cc90cbac01f5f94c5d1aecc5289ba1f

Cryptography 39.0.1 updates its dependency 'OpenSSL' to v3.0.8 to include security fixes.
https://github.com/pyca/cryptography/issues/8229

Cryptography 41.0.5 updates Windows, macOS, and Linux wheels to be compiled with OpenSSL 3.1.4, that includes a security fix.

Affected versions of the cryptography package are vulnerable to Improper Certificate Validation due to incomplete enforcement of DNS name constraints on peer names. The certificate validation logic applied DNS name constraints only to Subject Alternative Name (SAN) entries in child certificates, but did not apply the same checks to the peer name presented during validation, which allowed a mismatch between wildcard certificate matching and excluded subtree constraints.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Affected versions of the tornado package are vulnerable to Cookie Attribute Injection due to incomplete validation of values passed to the domain, path, and samesite arguments of the RequestHandler.set_cookie method. Specifically, semicolons are not rejected in these parameters, allowing crafted input to inject additional cookie attributes into the Set-Cookie header. An attacker who can influence cookie attribute values can override security-relevant attributes such as Secure, HttpOnly, or SameSite, potentially enabling session fixation or weakening cookie-based access controls.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Affected versions of the tornado package are vulnerable to Improper Input Validation due to incomplete validation of cookie attribute values. The RequestHandler.set_cookie method does not completely validate the domain, path, and samesite arguments, allowing semicolons in these fields that can inject unintended cookie attributes into the resulting Set-Cookie header.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Affected versions of the Tornado package are vulnerable to Denial of Service (DoS) due to uncontrolled multipart parsing complexity. The vulnerable multipart/form-data parser processes request bodies synchronously on the main thread, and before version 6.5.5 the only effective constraint on the number of multipart sections was max_body_size, which allows an attacker to submit a very large body containing an excessive number of parts and force expensive parsing work.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.