Threats Tagged 'cve-2026-54591'

AsyncSSH versions through 2.23.0 contain a path traversal vulnerability in the SCP client implementation. A malicious SSH server can send crafted filenames with directory traversal sequences to write arbitrary files outside the intended download directory. This allows overwriting critical user files such as ~/.bashrc, ~/.ssh/authorized_keys, and others, potentially leading to code execution. The vulnerability arises because filenames received from the server are not sanitized before being joined to the destination path. AsyncSSH 2.23.1 includes a fix for this issue.

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.