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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

Configuration 1 (hide)

cpe:2.3:a:asyncssh_project:asyncssh:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-17 19:17

Updated : 2026-07-30 14:36

NVD link : CVE-2026-45309

Mitre link : CVE-2026-45309

CVE.ORG link : CVE-2026-45309

JSON object : View

Products Affected

asyncssh_project

asyncssh

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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