CVE-2021-45105
Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontroll…
Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.
- Vendor
- apache
- Product
- log4j
- CVSS 3.1
- 5.9 (medium), scored by NVD (primary)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 3.1
- 5.9 (medium), scored by 134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2021-12-18
- NVD modified
- 2026-08-25
- NVD status
- Modified
Not in the CISA KEV catalogue at the last update.
EPSS
100% chance of exploitation in the next 30 days (percentile 99th)
FIRST EPSS, updated 17 Oct 2026. About EPSS
CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.
References
- www.openwall.com (Mailing List, Mitigation, Third Party Advisory)
- cert-portal.siemens.com (Third Party Advisory)
- cert-portal.siemens.com (Third Party Advisory)
- logging.apache.org (Release Notes, Vendor Advisory)
- psirt.global.sonicwall.com (Third Party Advisory)
- security.netapp.com (Third Party Advisory)
- tools.cisco.com (Third Party Advisory)
- www.debian.org (Third Party Advisory)
- www.kb.cert.org (Third Party Advisory, US Government Resource)
- www.oracle.com (Patch, Third Party Advisory)
- www.oracle.com (Patch, Third Party Advisory)
- www.oracle.com (Third Party Advisory)
Data last updated 18 Oct 2026. Sources: NVD API 2.0, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.