CVE-2021-45046

9.0 CRITICAL CISA KEV - Actively Exploited
Published: December 14, 2021 Modified: October 27, 2025
View on NVD

Description

It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in an information leak and remote code execution in some environments and local code execution in all environments. Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) fix this issue by removing support for message lookup patterns and disabling JNDI functionality by default.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/14/4
Source: security@apache.org
Mailing List Mitigation Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/15/3
Source: security@apache.org
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/18/1
Source: security@apache.org
Mailing List Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-397453.pdf
Source: security@apache.org
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf
Source: security@apache.org
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-661247.pdf
Source: security@apache.org
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-714170.pdf
Source: security@apache.org
Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EOKPQGV24RRBBI4TBZUDQMM4MEH7MXCY/
Source: security@apache.org
Mailing List Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SIG7FZULMNK2XF6FZRU4VWYDQXNMUGAJ/
Source: security@apache.org
Mailing List Release Notes
https://logging.apache.org/log4j/2.x/security.html
Source: security@apache.org
Mitigation Release Notes Vendor Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032
Source: security@apache.org
Third Party Advisory
https://security.gentoo.org/glsa/202310-16
Source: security@apache.org
Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd
Source: security@apache.org
Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2021-44228
Source: security@apache.org
Not Applicable
https://www.debian.org/security/2021/dsa-5022
Source: security@apache.org
Third Party Advisory
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00646.html
Source: security@apache.org
Third Party Advisory
https://www.kb.cert.org/vuls/id/930724
Source: security@apache.org
Third Party Advisory US Government Resource
https://www.oracle.com/security-alerts/alert-cve-2021-44228.html
Source: security@apache.org
Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html
Source: security@apache.org
Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.html
Source: security@apache.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html
Source: security@apache.org
Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/14/4
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Mitigation Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/15/3
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/12/18/1
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-397453.pdf
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-661247.pdf
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-714170.pdf
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EOKPQGV24RRBBI4TBZUDQMM4MEH7MXCY/
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SIG7FZULMNK2XF6FZRU4VWYDQXNMUGAJ/
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Release Notes
https://logging.apache.org/log4j/2.x/security.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mitigation Release Notes Vendor Advisory
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.gentoo.org/glsa/202310-16
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2021-44228
Source: af854a3a-2127-422b-91ae-364da2661108
Not Applicable
https://www.debian.org/security/2021/dsa-5022
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00646.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.kb.cert.org/vuls/id/930724
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory US Government Resource
https://www.oracle.com/security-alerts/alert-cve-2021-44228.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-45046
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

43 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.0 / 10.0
EPSS (Exploit Probability)
94.3%
100th percentile
Exploitation Status
Actively Exploited
Remediation due: 2023-05-22

Weaknesses (CWE)

CWE-917 CWE-917

Affected Vendors

intel debian cvat siemens fedoraproject apache sonicwall

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