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CISA Known Exploited Vulnerabilities

Apache Log4j2 Deserialization of Untrusted Data Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV
2023-05-01
Remediation due
2023-05-22
Ransomware
Known use

Required action
Apply updates per vendor instructions.

CISA notes
https://logging.apache.org/log4j/2.x/security.html; https://nvd.nist.gov/vuln/detail/CVE-2021-45046

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. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to 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. Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) fix this issue by removing support for message lookup patterns and disabling JNDI functionality by default.

Severity

CVSS 3.1 · CISA9 CRITICAL
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
SSVC · CISA-ADP
Exploitationactive
Automatableno
Technical impacttotal

Affected Products

VendorProductAffected versions
Apache Software FoundationApache Log4j
Apache Log4j2 to <2.16.0

References

21 Links

Record Details

Published
2021-12-14
Last updated
2025-10-21
Assigner (CNA)
apache
Credited to
-

CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.