AsyncSSH is a Python package which provides an asynchronous client and server implementation of the SSHv2 protocol on top of the Python asyncio framework. Prior to 2.23.0, AsyncSSH expands the OpenSSH-compatible AuthorizedKeysFile %u token in asyncssh/config.py, asyncssh/connection.py, asyncssh/auth_keys.py, and asyncssh/misc.py with the raw SSH username during pre-authentication server config reload, allowing a server configured with AuthorizedKeysFile authorized_keys/%u to read an authorized-keys file outside the intended directory when the SSH username contains /, \, or .. path traversal segments and authenticate with an attacker-selected key file. This issue is fixed in version 2.23.0.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://github.com/ronf/asyncssh/commit/2af2382cce946c959a378a62f257af253dc4ab51 Patch
- https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88 Patch
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h Exploit, Vendor Advisory
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h Exploit, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 8.2 · asyncssh_projectNVD modified 2026-10-24 20:10
Affected (CPE criteria) 1
cpe:2.3:a:asyncssh_project:asyncssh:*:*:*:*:*:*:*:*
References 4
- https://github.com/ronf/asyncssh/commit/2af2382cce946c959a378a62f257af253dc4ab51 Patch
- https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88 Patch
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h Exploit, Vendor Advisory
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h Exploit, Vendor Advisory