USN-4854-1: AsyncSSH vulnerability

15 March 2021

AsyncSSH would allow unintended access via a crafted client.

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

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.

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 18.04

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

References

Join the discussion

Need help with your security needs?

Ubuntu Pro provides up to ten-year security coverage for over 23,000 open-source packages within the Ubuntu Main and Universe repositories.

Talk to an expert to find out what would work best for you

Further reading