Expression Language Injection Affecting apache-log4j2 package, versions <2.16.0-1


Severity

Recommended
0.0
critical
0
10

Snyk's Security Team recommends NVD's CVSS assessment

    Threat Intelligence

    Exploit Maturity
    Mature
    EPSS
    97.3% (100th percentile)

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  • Snyk ID SNYK-DEBIANUNSTABLE-APACHELOG4J2-2320109
  • published 15 Dec 2021
  • disclosed 14 Dec 2021

How to fix?

Upgrade Debian:unstable apache-log4j2 to version 2.16.0-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream apache-log4j2 package and not the apache-log4j2 package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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.

References

CVSS Scores

version 3.1
Expand this section

NVD

Recommended
9 critical
  • Attack Vector (AV)
    Network
  • Attack Complexity (AC)
    High
  • Privileges Required (PR)
    None
  • User Interaction (UI)
    None
  • Scope (S)
    Changed
  • Confidentiality (C)
    High
  • Integrity (I)
    High
  • Availability (A)
    High
Expand this section

Red Hat

8.1 high