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Ubuntu 24.04 LTS USN-7108-1 Critical: AsyncSSH SSH Protocol Issues

ubuntu
Calendar Grey November 18, 2024
Scroller Ubuntu
Update on python-asyncssh vulnerabilities resolving security concerns for various Ubuntu versions with prompt fixes.
Several issues were fixed in AsyncSSH.

Summary

Several issues were fixed in AsyncSSH.

Software Description:

- 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)

Topics%20covered

Topics Covered

security advisory SSH protocol Ubuntu 20.04 Ubuntu 22.04 python-asyncssh Ubuntu 24.04 algorithm downgrade

Update Instructions

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

Ubuntu 24.04 LTS
   python3-asyncssh                2.10.1-2ubuntu0.1+esm1
                                   Available with Ubuntu Pro

Ubuntu 22.04 LTS
   python3-asyncssh                2.5.0-1ubuntu0.1

Ubuntu 20.04 LTS
   python3-asyncssh                1.12.2-1ubuntu0.2

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

References

  https://ubuntu.com/security/notices/USN-7108-1

  CVE-2023-46445, CVE-2023-46446

Severity
critical
Lowest
Low
Medium
High
Critical

Ubuntu Security Notice USN-7108-1

Topics%20covered

Topics Covered

security advisory SSH protocol Ubuntu 20.04 Ubuntu 22.04 python-asyncssh Ubuntu 24.04 algorithm downgrade

Package Information

https://launchpad.net/ubuntu/+source/python-asyncssh/1.12.2-1ubuntu0.2

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