Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Urllib3 1.24.3 includes a fix for CVE-2019-11236: CRLF injection is possible if the attacker controls the request parameter.
https://github.com/urllib3/urllib3/commit/5d523706c7b03f947dc50a7e783758a2bfff0532
https://github.com/urllib3/urllib3/issues/1553

Affected versions of urllib3 affected versions are vulnerable due to an issue where the authorization HTTP header is not removed when following a cross-origin redirect. This can result in credentials within the authorization header being exposed to unintended hosts or transmitted in cleartext. This vulnerability exists because of an incomplete fix for CVE-2018-20060, which addressed a similar issue case-sensitively.

Affected versions of urllib3 are vulnerable Improper Certificate Validation. Urllib3 mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to the use of the ssl_context, ca_certs, or ca_certs_dir argument.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Urllib3 1.24.3 includes a fix for CVE-2019-11236: CRLF injection is possible if the attacker controls the request parameter.
https://github.com/urllib3/urllib3/commit/5d523706c7b03f947dc50a7e783758a2bfff0532
https://github.com/urllib3/urllib3/issues/1553

Affected versions of urllib3 affected versions are vulnerable due to an issue where the authorization HTTP header is not removed when following a cross-origin redirect. This can result in credentials within the authorization header being exposed to unintended hosts or transmitted in cleartext. This vulnerability exists because of an incomplete fix for CVE-2018-20060, which addressed a similar issue case-sensitively.

Affected versions of urllib3 are vulnerable Improper Certificate Validation. Urllib3 mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to the use of the ssl_context, ca_certs, or ca_certs_dir argument.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Urllib3 1.24.3 includes a fix for CVE-2019-11236: CRLF injection is possible if the attacker controls the request parameter.
https://github.com/urllib3/urllib3/commit/5d523706c7b03f947dc50a7e783758a2bfff0532
https://github.com/urllib3/urllib3/issues/1553

Affected versions of urllib3 affected versions are vulnerable due to an issue where the authorization HTTP header is not removed when following a cross-origin redirect. This can result in credentials within the authorization header being exposed to unintended hosts or transmitted in cleartext. This vulnerability exists because of an incomplete fix for CVE-2018-20060, which addressed a similar issue case-sensitively.

Affected versions of urllib3 are vulnerable Improper Certificate Validation. Urllib3 mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to the use of the ssl_context, ca_certs, or ca_certs_dir argument.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Requests before 2.20.0 sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.