CVE-2021-45046: Apache Log4j2 Deserialization of Untrusted Data Vulnerability
Apache Log4j2 contains a deserialization of untrusted data vulnerability due to the incomplete fix of CVE-2021-44228, where the Thread Context Lookup Pattern is vulnerable to remote code execution in certain non-default configurations.
| Vendor | Apache |
|---|---|
| Product | Log4j2 |
| Date added to KEV | 2023-05-01 |
| Due date (BOD 22-01) | 2023-05-22 |
| Known ransomware campaign use | Known |
| CWE | CWE-917 |
| Required action | Apply updates per vendor instructions. |
What to do
- Identify every instance of Apache Log4j2 in your environment (asset inventory, EDR, vulnerability scanner).
- Apply CISA's required action: Apply updates per vendor instructions.
- Federal civilian agencies must act by 2023-05-22 under BOD 22-01; other organizations can use the same date as a target.
- Because ransomware use is known, check for signs of compromise and confirm backups are offline and tested.
- Check the vendor advisory and NVD entry linked below for affected versions, then record the fix in your change log.
This CVE is flagged by CISA as known to be used in ransomware campaigns. Rehearse your response before you need it: Ransomware tabletop exercise kit (Runbook Foundry).
Sources
- NVD entry for CVE-2021-45046 (severity scores, if any, live there)
- CISA KEV catalog entry
- https://logging.apache.org/log4j/2.x/security.html
- https://nvd.nist.gov/vuln/detail/CVE-2021-45046