USN-5203-1: Apache Log4j 2 vulnerability

19 December 2021

Apache Log4j 2 could be made to crash if it received specially crafted input.

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Releases

Packages

Details

Hideki Okamoto and Guy Lederfein discovered that Apache Log4j 2 did not
protect against infinite recursion in lookup evaluation. A remote attacker
could possibly use this issue to cause Apache Log4j 2 to crash, leading to
a denial of service.
Please see the following link for more information:
https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/Log4Shell

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 21.10
Ubuntu 21.04
Ubuntu 20.04

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

References

Related notices

  • USN-5222-1: liblog4j2-java-doc, liblog4j2-java, apache-log4j2