CVE-2026-54590

AsyncSSH is a Python package which provides an asynchronous client and server implementation of the SSHv2 protocol on top of the Python asyncio framework. Version 2.23.0 contains an incomplete fix for CVE-2026-45309 in SSHServerConfig._set_tokens that blocks /, , and .. before %u substitution in AuthorizedKeysFile but does not block a leading ~ or ${ENV}, allowing later expansion in _expand_val and Path(filename).expanduser() to escape the intended authorized-keys directory. This issue is fixed in version 2.23.1.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

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/3d515ba9ba0cd9990d248bdf62bcf05d51261a88
https://github.com/ronf/asyncssh/releases/tag/v2.23.1
https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh
https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh

Configurations

No configuration.

History

10 Jul 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh -~~	() https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh -

08 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 21:16

Updated : 2026-07-10 19:22

NVD link : CVE-2026-54590

Mitre link : CVE-2026-54590

CVE.ORG link : CVE-2026-54590

JSON object : View

Products Affected

No product.

CWE

CWE-22

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

CWE-639

Authorization Bypass Through User-Controlled Key

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