CISA KEV entry
CVE-2021-44228Apache Log4j2 Remote Code Execution Vulnerability
Apache Log4j2. Added to the CISA Known Exploited Vulnerabilities catalogue on 10 December 2021.
Data status: a source is stale
Last synced CISA catalogue version 2026.11.04 (released 4 November 2026) 1,768 entries Updated manually
- Date added
- 2021-12-10
- Federal due date
- 2021-12-24 14 days after it was added; passed at the sync of 2026-11-05
- Known ransomware use
- Known
- Forensic triage (BOD 26-04)
- No
- CVSS
- 10.0 Critical CVSS 3.1, scored by nvd@nist.gov
- EPSS
- 99.99% percentile 100.0, scored 2026-11-04
- CISA SSVC
- Exploitation active, automatable yes, technical impact total
- NVD status
- Analyzed published 2021-12-10
BOD 26-04 remediation window
With CISA's SSVC answers for this CVE (automatable: yes, technical impact: total), BOD 26-04 Table 1 gives 3 days and forensic triage on a publicly exposed asset (row 1) and 3 days and forensic triage on an asset that is not publicly exposed (row 9) S06. The catalogue due date, 14 days after the date added, was set before BOD 26-04 took effect on 10 June 2026 S06. The directive binds US federal civilian executive branch agencies only.
What CISA says
Short description
Apache Log4j2 contains a vulnerability where JNDI features do not protect against attacker-controlled JNDI-related endpoints, allowing for remote code execution.
Required action
For all affected software assets for which updates exist, the only acceptable remediation actions are: 1) Apply updates; OR 2) remove affected assets from agency networks. Temporary mitigations using one of the measures provided at https://www.cisa.gov/uscert/ed-22-02-apache-log4j-recommended-mitigation-measures are only acceptable until updates are available.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-44228
CWE in the catalogue
CWE-20, CWE-400, CWE-502
Official links
- CISA KEV catalogue entry cisa.gov
- NVD record nvd.nist.gov
Vendor advisory and patch links
References NVD tags Vendor Advisory or Patch, exactly as NVD lists them.
- https://logging.apache.org/log4j/2.x/security.html Release Notes, Vendor Advisory
- https://msrc-blog.microsoft.com/2021/12/11/microsofts-response-to-cve-2021-44228-apache-log4j2/ Patch, Third Party Advisory, Vendor Advisory
- https://www.oracle.com/security-alerts/cpuapr2022.html Patch, Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.html Patch, Third Party Advisory
Links in CISA's notes
NVD details
- CWE (NVD)
- CWE-20 by security@apache.org, CWE-400 by security@apache.org, CWE-502 by security@apache.org, CWE-917 by nvd@nist.gov
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H- CVSS versions in NVD
- V2, V31
- Last modified in NVD
- 2026-08-11T19:33:44.513
Where each value comes from
| Field | Source | Fetched, UTC | State |
|---|---|---|---|
| Catalogue fields | CISA KEV JSON, version 2026.11.04 | 2026-11-05 11:38 | current |
| NVD published, status, CVSS, CWE, vendor links | NVD CVE API 2.0; CVSS: NVD (nvd@nist.gov) | 2026-11-03 12:37 | current at 2026-11-05 11:38 |
| EPSS | FIRST EPSS API, scores of 2026-11-04 | 2026-11-05 11:38 | current |
| CISA SSVC | CISA ADP (via NVD), record of 2025-02-04 | 2026-11-03 12:37 | current |
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