1. Ubuntu Security Notices
  2. USN-4854-1

USN-4854-1: AsyncSSH vulnerability

Publication date

15 March 2021

Overview

AsyncSSH would allow unintended access via a crafted client.

Releases

Packages

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

Details

Matthijs Kooijman discovered that AsyncSSH server did not properly handle
authentication under certain conditions. An attacker with a specially
crafted client could use this vulnerability to skip authentication of SSH
sessions.

Matthijs Kooijman discovered that AsyncSSH server did not properly handle
authentication under certain conditions. An attacker with a specially
crafted client could use this vulnerability to skip authentication of SSH
sessions.

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
18.04 bionic python3-asyncssh –  1.11.1-1ubuntu0.1~esm1  

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References

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