Ssh-audit

This release features a new `--dheat` option to test targets for the DHEat denial-of-service attack (see [CVE-2002-20001](https://nvd.nist.gov/vuln/detail/CVE-2002-20001)). Also included are changes to custom policies that allow targets to surpass the specified security level; this allows for the creation of baseline policies (partial credit [yannik1015](https://github.com/yannik1015) and [Damian Szuberski](https://github.com/szubersk)).

This version is also available as a PyPI package (`pip3 install ssh-audit`), Docker image (`docker pull positronsecurity/ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (see below, though be aware that sometimes Windows Defender inappropriately detects it as malware!).

- Added implementation of the DHEat denial-of-service attack (see `--dheat` option; [CVE-2002-20001](https://nvd.nist.gov/vuln/detail/CVE-2002-20001)).
- Expanded filter of CBC ciphers to flag for the Terrapin vulnerability. It now includes more rarely found ciphers.
- Fixed parsing of `ecdsa-sha2-nistp*` CA signatures on host keys. Additionally, they are now flagged as potentially back-doored, just as standard host keys are.
- Gracefully handle rare exceptions (i.e.: crashes) while performing GEX tests.
- The built-in man page (`-m`, `--manual`) is now available on Docker, PyPI, and Snap builds, in addition to the Windows build.
- Snap builds are now architecture-independent.
- Changed Docker base image from `python:3-slim` to `python:3-alpine`, resulting in a 59% reduction in image size; credit [Daniel Thamdrup](https://github.com/dallemon).
- Added built-in policies for Amazon Linux 2023, Debian 12, OpenSSH 9.7, and Rocky Linux 9.
- Built-in policies now include a change log (use `-L -v` to view them).
- Custom policies now support the `allow_algorithm_subset_and_reordering` directive to allow targets to pass with a subset and/or re-ordered list of host keys, kex, ciphers, and MACs. This allows for the creation of a baseline policy where targets can optionally implement stricter controls; partial credit [yannik1015](https://github.com/yannik1015).
- Custom policies now support the `allow_larger_keys` directive to allow targets to pass with larger host keys, CA keys, and Diffie-Hellman keys. This allows for the creation of a baseline policy where targets can optionally implement stricter controls; partial credit [Damian Szuberski](https://github.com/szubersk).
- Color output is disabled if the `NO_COLOR` environment variable is set (see https://no-color.org/).
- Added 1 new key exchange algorithm: `gss-nistp384-sha384-*`.
- Added 1 new cipher: `aes128-ocblibassh.org`.

This release features tests for the Terrapin message prefix truncation vulnerability in the SSH protocol ([CVE-2023-48795](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-48795)), along with other minor enhancements and fixes.

This version is also available as a PyPI package (`pip3 install ssh-audit`), Docker image (`docker pull positronsecurity/ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (see below, though be aware that sometimes Windows Defender inappropriately detects it as malware!).

The full change log is:
- Added test for the Terrapin message prefix truncation vulnerability ([CVE-2023-48795](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-48795)).
- Dropped support for Python 3.7 (EOL was reached in June 2023).
- Added Python 3.12 support.
- In server policies, reduced expected DH modulus sizes from 4096 to 3072 to match the [online hardening guides](https://ssh-audit.com/hardening_guides.html) (note that 3072-bit moduli provide the equivalent of 128-bit symmetric security).
- In Ubuntu 22.04 client policy, moved host key types `sk-ssh-ed25519openssh.com` and `ssh-ed25519` to the end of all certificate types.
- Updated Ubuntu Server & Client policies for 20.04 and 22.04 to account for key exchange list changes due to Terrapin vulnerability patches.
- Re-organized option host key types for OpenSSH 9.2 server policy to correspond with updated Debian 12 hardening guide.
- Added built-in policies for OpenSSH 9.5 and 9.6.
- Added an `additional_notes` field to the JSON output.

This release includes important fixes for multiple-host scans, improved Diffie-Hellman group exchange auditing, and the inclusion of algorithm notes into the JSON output (note that this changes the schema of the banner protocol, "enc", and "mac" fields). Support for 49 new algorithms were also added!

This version is also available as a PyPI package (`pip3 install ssh-audit`), Docker image (`docker pull positronsecurity/ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (see below, though be aware that sometimes Windows Defender inappropriately detects it as malware!).

The full change log is:
- Results from concurrent scans against multiple hosts are no longer improperly combined; bug discovered by [Adam Russell](https://github.com/thecliguy).
- Hostname resolution failure no longer causes scans against multiple hosts to terminate unexpectedly; credit [Dani Cuesta](https://github.com/daniel-cues).
- Algorithm recommendations resulting from warnings are now printed in yellow instead of red; credit [Adam Russell](https://github.com/thecliguy).
- Added failure, warning, and info notes to JSON output (note that this results in a breaking change to the banner protocol, "enc", and "mac" fields); credit [Bareq Al-Azzawi](https://github.com/BareqAZ).
- Docker Makefile now creates multi-arch builds for amd64, arm64, and armv7; credit [Sebastian Cohnen](https://github.com/tisba).
- Fixed crash during GEX tests.
- Refined GEX testing against OpenSSH servers: when the fallback mechanism is suspected of being triggered, perform an additional test to obtain more accurate results.
- The color of all notes will be printed in green when the related algorithm is rated good.
- Prioritized host key certificate algorithms for Ubuntu 22.04 LTS client policy.
- Marked all NIST K-, B-, and T-curves as unproven since they are so rarely used.
- Added built-in policy for OpenSSH 9.4.
- Added 12 new host keys: `ecdsa-sha2-curve25519`, `ecdsa-sha2-nistb233`, `ecdsa-sha2-nistb409`, `ecdsa-sha2-nistk163`, `ecdsa-sha2-nistk233`, `ecdsa-sha2-nistk283`, `ecdsa-sha2-nistk409`, `ecdsa-sha2-nistp224`, `ecdsa-sha2-nistp192`, `ecdsa-sha2-nistt571`, `ssh-dsa`, `x509v3-sign-rsa-sha256`.
- Added 15 new key exchanges: `curve448-sha512libssh.org`, `ecdh-nistp256-kyber-512r3-sha256-d00openquantumsafe.org`, `ecdh-nistp384-kyber-768r3-sha384-d00openquantumsafe.org`, `ecdh-nistp521-kyber-1024r3-sha512-d00openquantumsafe.org`, `ecdh-sha2-brainpoolp256r1genua.de`, `ecdh-sha2-brainpoolp384r1genua.de`, `ecdh-sha2-brainpoolp521r1genua.de`, `kexAlgoDH14SHA1`, `kexAlgoDH1SHA1`, `kexAlgoECDH256`, `kexAlgoECDH384`, `kexAlgoECDH521`, `sm2kep-sha2-nistp256`, `x25519-kyber-512r3-sha256-d00amazon.com`, `x25519-kyber512-sha512aws.amazon.com`.
- Added 8 new ciphers: `aes192-gcmopenssh.com`, `cast128-12-cbc`, `cast128-12-cfb`, `cast128-12-ecb`, `cast128-12-ofb`, `des-cfb`, `des-ecb`, `des-ofb`.
- Added 14 new MACs: `cbcmac-3des`, `cbcmac-aes`, `cbcmac-blowfish`, `cbcmac-des`, `cbcmac-rijndael`, `cbcmac-twofish`, `hmac-sha256-96`, `md5`, `md5-8`, `ripemd160`, `ripemd160-8`, `sha1`, `sha1-8`, `umac-128`.

This release includes many new features, including granular GEX modulus tests (credit [Adam Russell](https://github.com/thecliguy)), support for mixed host key/CA key certificates (i.e.: RSA host keys signed by ED25519 CAs), warnings for 2048-bit moduli, and more descriptive algorithm notes. Support for _112 new algorithms_ were also added!

Note that this version is also available as a PyPI package (`pip3 install ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (see below, though be aware that sometimes Windows Defender inappropriately detects it as malware!).

The full change log is:
- Dropped support for Python 3.6, as it reached EOL at the end of 2021.
- Added Ubuntu Server & Client 22.04 hardening policies.
- Removed experimental warning tag from `sntrup761x25519-sha512openssh.com`.
- Updated CVE database; credit [Alexandre Zanni](https://github.com/noraj).
- Added `-g` and `--gex-test` for granular GEX modulus size tests; credit [Adam Russell](https://github.com/thecliguy).
- Snap packages now print more user-friendly error messages when permission errors are encountered.
- JSON 'target' field now always includes port number; credit [tomatohater1337](https://github.com/tomatohater1337).
- JSON output now includes recommendations and CVE data.
- Mixed host key/CA key types (i.e.: RSA host keys signed with ED25519 CAs, etc.) are now properly handled.
- Warnings are now printed for 2048-bit moduli; partial credit [Adam Russell](https://github.com/thecliguy).
- SHA-1 algorithms now cause failures.
- CBC mode ciphers are now warnings instead of failures.
- Generic failure/warning messages replaced with more specific reasons (i.e.: 'using weak cipher' => 'using broken RC4 cipher').
- Updated built-in policies to include missing host key size information.
- Added built-in policies for OpenSSH 8.8, 8.9, 9.0, 9.1, 9.2, and 9.3.
- Added 33 new host keys: `dsa2048-sha224libassh.org`, `dsa2048-sha256libassh.org`, `dsa3072-sha256libassh.org`, `ecdsa-sha2-1.3.132.0.10-cert-v01openssh.com`, `eddsa-e382-shake256libassh.org`, `eddsa-e521-shake256libassh.org`, `null`, `pgp-sign-dss`, `pgp-sign-rsa`, `spki-sign-dss`, `spki-sign-rsa`, `ssh-dss-sha224ssh.com`, `ssh-dss-sha384ssh.com`, `ssh-dss-sha512ssh.com`, `ssh-ed448-cert-v01openssh.com`, `ssh-rsa-sha224ssh.com`, `ssh-rsa-sha2-256`, `ssh-rsa-sha2-512`, `ssh-rsa-sha384ssh.com`, `ssh-rsa-sha512ssh.com`, `ssh-xmss-cert-v01openssh.com`, `ssh-xmssopenssh.com`, `webauthn-sk-ecdsa-sha2-nistp256openssh.com`, `x509v3-ecdsa-sha2-1.3.132.0.10`, `x509v3-sign-dss-sha1`, `x509v3-sign-dss-sha224ssh.com`, `x509v3-sign-dss-sha256ssh.com`, `x509v3-sign-dss-sha384ssh.com`, `x509v3-sign-dss-sha512ssh.com`, `x509v3-sign-rsa-sha1`, `x509v3-sign-rsa-sha224ssh.com`, `x509v3-sign-rsa-sha384ssh.com`, `x509v3-sign-rsa-sha512ssh.com`.
- Added 46 new key exchanges: `diffie-hellman-group14-sha224ssh.com`, `diffie-hellman_group17-sha512`, `diffie-hellman-group-exchange-sha224ssh.com`, `diffie-hellman-group-exchange-sha384ssh.com`, `ecdh-sha2-1.2.840.10045.3.1.1`, `ecdh-sha2-1.2.840.10045.3.1.7`, `ecdh-sha2-1.3.132.0.1`, `ecdh-sha2-1.3.132.0.16`, `ecdh-sha2-1.3.132.0.26`, `ecdh-sha2-1.3.132.0.27`, `ecdh-sha2-1.3.132.0.33`, `ecdh-sha2-1.3.132.0.34`, `ecdh-sha2-1.3.132.0.35`, `ecdh-sha2-1.3.132.0.36`, `ecdh-sha2-1.3.132.0.37`, `ecdh-sha2-1.3.132.0.38`, `ecdh-sha2-4MHB+NBt3AlaSRQ7MnB4cg==`, `ecdh-sha2-5pPrSUQtIaTjUSt5VZNBjg==`, `ecdh-sha2-9UzNcgwTlEnSCECZa7V1mw==`, `ecdh-sha2-D3FefCjYoJ/kfXgAyLddYA==`, `ecdh-sha2-h/SsxnLCtRBh7I9ATyeB3A==`, `ecdh-sha2-m/FtSAmrV4j/Wy6RVUaK7A==`, `ecdh-sha2-mNVwCXAoS1HGmHpLvBC94w==`, `ecdh-sha2-qCbG5Cn/jjsZ7nBeR7EnOA==`, `ecdh-sha2-qcFQaMAMGhTziMT0z+Tuzw==`, `ecdh-sha2-VqBg4QRPjxx1EXZdV0GdWQ==`, `ecdh-sha2-wiRIU8TKjMZ418sMqlqtvQ==`, `ecdh-sha2-zD/b3hu/71952ArpUG4OjQ==`, `ecmqv-sha2`, `gss-13.3.132.0.10-sha256-*`, `gss-curve25519-sha256-*`, `gss-curve448-sha512-*`, `gss-gex-sha1-*`, `gss-gex-sha256-*`, `gss-group14-sha1-*`, `gss-group14-sha256-*`, `gss-group15-sha512-*`, `gss-group16-sha512-*`, `gss-group17-sha512-*`, `gss-group18-sha512-*`, `gss-group1-sha1-*`, `gss-nistp256-sha256-*`, `gss-nistp384-sha256-*`, `gss-nistp521-sha512-*`, `m383-sha384libassh.org`, `m511-sha512libassh.org`.
- Added 28 new ciphers: `3des-cfb`, `3des-ecb`, `3des-ofb`, `blowfish-cfb`, `blowfish-ecb`, `blowfish-ofb`, `camellia128-cbcopenssh.org`, `camellia128-ctropenssh.org`, `camellia192-cbcopenssh.org`, `camellia192-ctropenssh.org`, `camellia256-cbcopenssh.org`, `camellia256-ctropenssh.org`, `cast128-cfb`, `cast128-ecb`, `cast128-ofb`, `cast128-12-cbcssh.com`, `idea-cfb`, `idea-ecb`, `idea-ofb`, `rijndael-cbcssh.com`, `seed-ctrssh.com`, `serpent128-gcmlibassh.org`, `serpent256-gcmlibassh.org`, `twofish128-gcmlibassh.org`, `twofish256-gcmlibassh.org`, `twofish-cfb`, `twofish-ecb`, `twofish-ofb`
- Added 5 new MACs: `hmac-sha1-96openssh.com`, `hmac-sha224ssh.com`, `hmac-sha256-2ssh.com`, `hmac-sha384ssh.com`, `hmac-whirlpool`.

This release fixes some minor bugs, and adds some minor features.

Please note that this version is also available as a PyPI package (`pip3 install ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (below, though be aware that Windows Defender inappropriately detects it as malware!).

The full change log is:
- Fixed crash when running host key tests.
- Handles server connection failures more gracefully.
- Now prints JSON with indents when `-jj` is used (useful for debugging).
- Added MD5 fingerprints to verbose output.
- Added `-d`/`--debug` option for getting debugging output; credit [Adam Russell](https://github.com/thecliguy).
- Updated JSON output to include MD5 fingerprints. Note that this results in a breaking change in the 'fingerprints' dictionary format.
- Updated OpenSSH 8.1 (and earlier) policies to include `rsa-sha2-512` and `rsa-sha2-256`.
- Added OpenSSH v8.6 & v8.7 policies.
- Added 3 new key exchanges: `gss-gex-sha1-eipGX3TCiQSrx573bT1o1Q==`, `gss-group1-sha1-eipGX3TCiQSrx573bT1o1Q==`, and `gss-group14-sha1-eipGX3TCiQSrx573bT1o1Q==`.
- Added 3 new MACs: `hmac-ripemd160-96`, `AEAD_AES_128_GCM`, and `AEAD_AES_256_GCM`.

This is primarily a bug-fix release.

Please note that this version is also available as a PyPI package (`pip3 install ssh-audit`), Snap package (`snap install ssh-audit`), or as a Windows executable (below).

The full change log is:

- Added multi-threaded scanning support.
- Added built-in Windows manual page (see `-m`/`--manual`); credit [Adam Russell](https://github.com/thecliguy).
- Added version check for OpenSSH user enumeration (CVE-2018-15473).
- Added deprecation note to host key types based on SHA-1.
- Added extra warnings for SSHv1.
- Added built-in hardened OpenSSH v8.5 policy.
- Upgraded warnings to failures for host key types based on SHA-1.
- Fixed crash when receiving unexpected response during host key test.
- Fixed hang against older Cisco devices during host key test & gex test.
- Fixed improper termination while scanning multiple targets when one target returns an error.
- Dropped support for Python 3.5 (which reached EOL in Sept. 2020).
- Added 1 new key exchange: `sntrup761x25519-sha512openssh.com`.