CVE-2021-45046
CVSS v3
9
CRITICAL
EPSS Score
94.3 %
exploit probability
CISA KEV
Yes
known exploited
Exploitation
—
SSVC status
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, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in an information leak and remote code execution in some environments and local code execution in all environments. Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) fix this issue by removing support for message lookup patterns and disabling JNDI functionality by default.
CISA Known Exploited Vulnerability
- Date Added
- 2023-05-01
- Patch Due Date
- 2023-05-22
- Ransomware Use
- Known
Technical details
- Published
- 2021-12-14
Frequently asked questions
What is CVE-2021-45046?
It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${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.
Is CVE-2021-45046 actively exploited?
Yes. CVE-2021-45046 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2023-05-22.
What is the CVSS score for CVE-2021-45046?
CVE-2021-45046 has a CVSS v3 base score of 9 (CRITICAL severity).
Is CVE-2021-45046 affecting your environment?
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