Apache Log4j2 Deserialization of Untrusted Data Vulnerability

A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2023-05-22 under CISA BOD 22-01.

This is a Software Vulnerability (CWE-917) (CWE-917) vulnerability in Apache Log4j2. 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. Exploitation requires remote network access, higher attack complexity, no authentication required, and no user interaction required.

Probably yes if any of these apply:

CISA confirms this CVE has been used in known ransomware campaigns. Added to the KEV catalog on 2023-05-01; federal agencies required to remediate by 2023-05-22.