USN-6279-1: OpenSSH update

9 August 2023

A hardening measure was added to OpenSSH.

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Releases

Packages

  • openssh - secure shell (SSH) for secure access to remote machines

Details

It was discovered that OpenSSH has an observable discrepancy leading to an
information leak in the algorithm negotiation. This update mitigates the
issue by tweaking the client hostkey preference ordering algorithm to
prefer the default ordering if the user has a key that matches the
best-preference default algorithm.

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 20.04
Ubuntu 18.04
Ubuntu 16.04
Ubuntu 14.04

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

References

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Further reading