CVE-2026-45309
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.
- CVSS 4.0
- 8.2
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS
- 0.6% chance of exploitation in the next 30 days; higher than 47% of CVEs (scores of 2026-10-25)
- CWE
- CWE-22
- Published
- Modified
- Record from
- the NVD, synced
Affected
- asyncssh_project:asyncssh
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-g794-3fmp-753h | PyPI | asyncssh | >=2.22.0 <2.23.0 | 2.23.0 |
| PYSEC-2026-2384 | PyPI | asyncssh | >=2.22.0 <2.23.0 | 2.23.0 |
References
- https://github.com/ronf/asyncssh/commit/2af2382cce946c959a378a62f257af253dc4ab51
- https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h
- https://github.com/ronf/asyncssh/security/advisories/GHSA-g794-3fmp-753h