An Apache Log4j 1.2 security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, 21.04, and 21.10.

USN-5223-1: Apache Log4j 1.2 vulnerability

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Ubuntu Security Notice USN-5223-1
January 12, 2022

apache-log4j1.2 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 21.10
- Ubuntu 21.04
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Apache Log4j 1.2 could be made to crash or run programs if it received specially
crafted input.

Software Description:
- apache-log4j1.2: Java-based open-source logging tool

Details:

It was discovered that Apache Log4j 1.2 was vulnerable to deserialization of
untrusted data if the configuration file was editable. An attacker could use
this vulnerability to cause a DoS or possibly execute arbitrary code.

Update instructions:

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

Ubuntu 21.10:
liblog4j1.2-java 1.2.17-10ubuntu0.21.10.1

Ubuntu 21.04:
liblog4j1.2-java 1.2.17-10ubuntu0.21.04.1

Ubuntu 20.04 LTS:
liblog4j1.2-java 1.2.17-9ubuntu0.1

Ubuntu 18.04 LTS:
liblog4j1.2-java 1.2.17-8+deb10u1ubuntu0.1

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

References:
https://ubuntu.com/security/notices/USN-5223-1
CVE-2021-4104

Package Information:
https://launchpad.net/ubuntu/+source/apache-log4j1.2/1.2.17-10ubuntu0.21.10.1
https://launchpad.net/ubuntu/+source/apache-log4j1.2/1.2.17-10ubuntu0.21.04.1
https://launchpad.net/ubuntu/+source/apache-log4j1.2/1.2.17-9ubuntu0.1
https://launchpad.net/ubuntu/+source/apache-log4j1.2/1.2.17-8+deb10u1ubuntu0.1