USN-7108-1: AsyncSSH vulnerabilities

18 November 2024

Several issues were fixed in AsyncSSH.

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Releases

Packages

  • python-asyncssh - asyncio-based client and server implementation of SSHv2 protocol

Details

Fabian Bäumer, Marcus Brinkmann, and Jörg Schwenk discovered that AsyncSSH
did not properly handle the extension info message. An attacker able to
intercept communications could possibly use this issue to downgrade
the algorithm used for client authentication. (CVE-2023-46445)

Fabian Bäumer, Marcus Brinkmann, and Jörg Schwenk discovered that AsyncSSH
did not properly handle the user authentication request message. An
attacker could possibly use this issue to control the remote end of an SSH
client session via packet injection/removal and shell emulation.
(CVE-2023-46446)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 24.04
Ubuntu 22.04
Ubuntu 20.04

In general, a standard system update will make all the necessary changes.

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