CVE Database · CVE-2021-45046
CVSS v3.1
9.0
EPSS
99.98%
Published
Dec 14, 2021
Modified
Oct 27, 2025
CISA Known Exploited Vulnerability
Added: 2023-05-01 · Due: 2023-05-22
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Public PoC / Exploit (10)
All weaponized →Links to public security research (Exploit-DB, Nuclei, Trickest, GitHub) for defensive use only.
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.
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HWeaknesses (CWE)
Affected Products (96)
References (20)
...and 46 more