An apache-log4j2 security update has been released for Debian GNU/Linux 10 and 11.

DSA 5024-1: apache-log4j2 security update

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Debian Security Advisory DSA-5024-1 security@debian.org
  https://www.debian.org/security/ Markus Koschany
December 18, 2021   https://www.debian.org/security/faq
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Package : apache-log4j2
CVE ID : CVE-2021-45105
Debian Bug : 1001891

It was found that Apache Log4j2, a Logging Framework for Java, did not protect
from uncontrolled recursion from self-referential lookups. When the logging
configuration uses a non-default Pattern Layout with a Context Lookup (for
example, $${ctx:loginId}), attackers with control over Thread Context Map (MDC)
input data can craft malicious input data that contains a recursive lookup,
resulting in a denial of service.

For the oldstable distribution (buster), this problem has been fixed
in version 2.17.0-1~deb10u1.

For the stable distribution (bullseye), this problem has been fixed in
version 2.17.0-1~deb11u1.

We recommend that you upgrade your apache-log4j2 packages.

For the detailed security status of apache-log4j2 please refer to
its security tracker page at:
  https://security-tracker.debian.org/tracker/apache-log4j2

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at:   https://www.debian.org/security/