High severity · published Jul 8, 2026
CVE-2026-54591
AsyncSSH: SCP Path Traversal to Arbitrary File Write
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
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 2.23.1, a malicious SSH server can write arbitrary files on the asyncssh SCP client's filesystem by sending filenames containing ../ traversal sequences because _parse_cd_args in scp.py returns server-provided names verbatim and _recv_files joins them to the destination path without enforcing the target directory boundary. This issue is fixed in version 2.23.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
asyncssh · ronf
< 2.23.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54591
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-54591
github.com
https://github.com/ronf/asyncssh/commit/d730803b8e4e94c20c7580d90f94d1e05f9f58de
github.com
https://github.com/ronf/asyncssh/releases/tag/v2.23.1
github.com
https://github.com/ronf/asyncssh/security/advisories/GHSA-2wxc-x7rj-hg8f
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