PT-2026-56577 · Ronf · Asyncssh

Published 2026-07-08 · Updated 2026-07-08 · CVE-2026-54590

Mitre

CVSS v3.1

5.9

Medium

Base vector

AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

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.

Fix

IDOR

Path traversal

Weakness Enumeration

CWE-639

CWE-22

Related Identifiers

CVE-2026-54590

Affected Products

Asyncssh

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-54590 · Security Note
• https://github.com/ronf/asyncssh/commit/3d515ba9ba0cd9990d248bdf62bcf05d51261a88 · Note
• https://github.com/ronf/asyncssh/security/advisories/GHSA-qr67-gv47-xwwh · Note
• https://github.com/ronf/asyncssh/releases/tag/v2.23.1 · Note