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Apache Log4j Core: CVE-2021-45105: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation

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Apache Log4j Core: CVE-2021-45105: Apache Log4j2 does not always protect from infinite recursion in lookup evaluation

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:N/A:P)
Published
12/17/2021
Created
12/21/2021
Added
12/20/2021
Modified
07/18/2022

Description

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 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 StackOverflowError that will terminate the process. This is also known as a DOS (Denial of Service) attack.

Solution(s)

  • apache-log4j-core-upgrade-2_12_3
  • apache-log4j-core-upgrade-2_17
  • apache-log4j-core-upgrade-2_3_1

References

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