[USN-5203-1] Apache Log4j 2 vulnerability

========================================================================== Ubuntu Security Notice USN-5203-1 December 19, 2021
apache-log4j2 vulnerability ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 21.10 – Ubuntu 21.04 – Ubuntu 20.04 LTS
Summary:
Apache Log4j 2 could be made to crash if it received specially crafted input.
Software Description: – apache-log4j2: Apache Log4j – Logging Framework for Java
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.
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 21.10: liblog4j2-java 2.17.0-0.21.10.1
Ubuntu 21.04: liblog4j2-java 2.17.0-0.21.04.1
Ubuntu 20.04 LTS: liblog4j2-java 2.17.0-0.20.04.1
In general, a standard system update will make all the necessary changes.
References: ubuntu.com/security/notices/USN-5203-1 CVE-2021-45105
Package Information: launchpad.net/ubuntu/+source/apache-log4j2/2.17.0-0.21.10.1 launchpad.net/ubuntu/+source/apache-log4j2/2.17.0-0.21.04.1 launchpad.net/ubuntu/+source/apache-log4j2/2.17.0-0.20.04.1