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

Source: https://junglewise.ai/threats/cve-2021-45046-apache-log4j2-deserialization-of-untrusted-data-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-12-14. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

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](https://junglewise.ai/threats/technologies/log4j2), [org.apache.logging.log4j:log4j-core (Maven)](https://junglewise.ai/threats/technologies/org-apache-logging-log4j-log4j-core), [org.ops4j.pax.logging:pax-logging-log4j2 (Maven)](https://junglewise.ai/threats/technologies/org-ops4j-pax-logging-pax-logging-log4j2). Vendors: [Apache](https://junglewise.ai/threats/vendors/apache), [Maven](https://junglewise.ai/threats/vendors/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

  ```sh
  # 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

  ```sh
  # 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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- [Apache Log4j 1.x (EOL) allows Denial of Service (DoS)](https://junglewise.ai/threats/cve-2023-26464-apache-log4j-1-x-eol-allows-denial-of-service-dos)