CVE-2021-45046: Incomplete fix for Apache Log4j vulnerability

CVE-2021-45046 · Severity: critical · CVSS 9 · Exploited in the wild · Published 2021-12-14

Apache Log4j2 contains an incomplete fix for CVE-2021-44228, allowing for deserialization of untrusted data. In certain non-default configurations, attackers can use JNDI Lookup patterns via Thread Context Map input to achieve remote code execution or information leaks.

Technologies: Apache Log4j2, org.apache.logging.log4j:log4j-core (Maven), org.ops4j.pax.logging:pax-logging-log4j2 (Maven). Vendors: Apache, Maven.

Quick answers

Is CVE-2021-45046 exploited in the wild?
Yes. CVE-2021-45046 is known to be exploited in the wild, first recorded on 1 May 2023. Treat it as urgent.
How severe is CVE-2021-45046?
Critical severity, with a CVSS score of 9, published 14 December 2021.
Which products and versions are affected?
org.apache.logging.log4j:log4j-core (Maven) ECOSYSTEM:introduced=2.13.0,fixed=2.16.0; org.ops4j.pax.logging:pax-logging-log4j2 (Maven) ECOSYSTEM:introduced=1.8.0,fixed=1.9.2.
Is there a fix for CVE-2021-45046?
Yes. org.apache.logging.log4j:log4j-core (Maven): upgrade to 2.16.0 or later; org.ops4j.pax.logging:pax-logging-log4j2 (Maven): upgrade to 1.9.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2021-45046 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2021-45046?
Check whether you run Apache Log4j2, org.apache.logging.log4j:log4j-core (Maven) or org.ops4j.pax.logging:pax-logging-log4j2 (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • org.apache.logging.log4j:log4j-core (Maven): upgrade to 2.16.0 or later
    # set org.apache.logging.log4j:log4j-core to 2.16.0 in your pom.xml or build.gradle
  • org.ops4j.pax.logging:pax-logging-log4j2 (Maven): upgrade to 1.9.2 or later
    # set org.ops4j.pax.logging:pax-logging-log4j2 to 1.9.2 in your pom.xml or build.gradle

Affected products

  • Apache Log4j 2 2.0-beta9 to 2.15.0

Identifiers

  • CVE-2021-45046
  • GHSA-7rjr-3q55-vv33

Timeline

  • 2021-12-14: disclosed: Initial public disclosure via mailing lists.
  • 2023-05-01: kev added: Added to CISA's Known Exploited Vulnerabilities Catalog.
  • 2021-12-16: patched: Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) released to fix the issue.
  • 2023-05-01: exploited: Reported as exploited in the wild.

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