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Apache Log4j Core: CVE-2021-45046: Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations

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Apache Log4j Core: CVE-2021-45046: Apache Log4j2 Thread Context Lookup Pattern vulnerable to remote code execution in certain non-default configurations

Severity
5
CVSS
(AV:N/AC:H/Au:N/C:P/I:P/A:P)
Published
12/14/2021
Created
12/15/2021
Added
12/14/2021
Modified
05/02/2023

Description

It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. 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 using a JNDI Lookup pattern, resulting in an information leak and remote code execution in some environments and local code execution in all environments; remote code execution has been demonstrated on macOS but no other tested environments.

Solution(s)

  • apache-log4j-core-upgrade-2_16
  • apache-log4j-core-upgrade-2_12_2
  • apache-log4j-core-upgrade-2_3_1

References

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