CVE-2021-45105
5.9 MEDIUMApache 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-refer...
Published: 2021-12-18 · Last updated: 2026-05-29
Severity and scoring
- CVSS
- 5.9 MEDIUM
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- CWE
- CWE-20, CWE-674
Affected products
| Vendor | Product |
|---|---|
| apache | 6bk1602-0aa12-0tp0_firmware, 6bk1602-0aa22-0tp0_firmware, 6bk1602-0aa32-0tp0_firmware |
| debian | 6bk1602-0aa12-0tp0_firmware, 6bk1602-0aa22-0tp0_firmware, 6bk1602-0aa32-0tp0_firmware |
| netapp | 6bk1602-0aa12-0tp0_firmware, 6bk1602-0aa22-0tp0_firmware, 6bk1602-0aa32-0tp0_firmware |
| oracle | 6bk1602-0aa12-0tp0_firmware, 6bk1602-0aa22-0tp0_firmware, 6bk1602-0aa32-0tp0_firmware |
| sonicwall | 6bk1602-0aa12-0tp0_firmware, 6bk1602-0aa22-0tp0_firmware, 6bk1602-0aa32-0tp0_firmware |
Description
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.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-45105
- [Other]http://www.openwall.com/lists/oss-security/2021/12/19/1
- [Other]https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf
- [Other]https://cert-portal.siemens.com/productcert/pdf/ssa-501673.pdf
- [Vendor advisory]https://logging.apache.org/log4j/2.x/security.html
- [Other]https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032
- [Other]https://security.netapp.com/advisory/ntap-20211218-0001/
- [Other]https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd
- [Other]https://www.debian.org/security/2021/dsa-5024
- [Other]https://www.kb.cert.org/vuls/id/930724
- [Patch]https://www.oracle.com/security-alerts/cpuapr2022.html
- [Patch]https://www.oracle.com/security-alerts/cpujan2022.html
- [Other]https://www.oracle.com/security-alerts/cpujul2022.html
- [Other]https://www.zerodayinitiative.com/advisories/ZDI-21-1541/
- [Other]http://www.openwall.com/lists/oss-security/2021/12/19/1
- [Other]https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf
- [Other]https://cert-portal.siemens.com/productcert/pdf/ssa-501673.pdf
- [Vendor advisory]https://logging.apache.org/log4j/2.x/security.html
- [Other]https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032
- [Other]https://security.netapp.com/advisory/ntap-20211218-0001/
- [Other]https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd
- [Other]https://www.debian.org/security/2021/dsa-5024
- [Other]https://www.kb.cert.org/vuls/id/930724
- [Patch]https://www.oracle.com/security-alerts/cpuapr2022.html
- [Patch]https://www.oracle.com/security-alerts/cpujan2022.html
- [Other]https://www.oracle.com/security-alerts/cpujul2022.html
- [Other]https://www.zerodayinitiative.com/advisories/ZDI-21-1541/
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