Expression Language Injection The advisory has been revoked - it doesn't affect any version of package log4j-core.src (opens in a new tab)
Threat Intelligence
Snyk has reported that there have been attempts or successful attacks targeting this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-RHEL10-LOG4JCORESRC-15340297
- published25 Feb 2026
- disclosed14 Dec 2021
Introduced: 14 Dec 2021
CVE-2021-45046 (opens in a new tab)Amendment
The Red Hat security team deemed this advisory irrelevant for RHEL:10.
NVD Description
Note: Versions mentioned in the description apply only to the upstream log4j-core.src package and not the log4j-core.src package as distributed by RHEL.
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.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2032580
- https://access.redhat.com/security/cve/CVE-2021-44228
- https://access.redhat.com/security/cve/CVE-2021-45046
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/EOKPQGV24RRBBI4TBZUDQMM4MEH7MXCY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SIG7FZULMNK2XF6FZRU4VWYDQXNMUGAJ/
- http://www.openwall.com/lists/oss-security/2021/12/14/4
- http://www.openwall.com/lists/oss-security/2021/12/15/3
- http://www.openwall.com/lists/oss-security/2021/12/18/1
- https://cert-portal.siemens.com/productcert/pdf/ssa-397453.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-479842.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-661247.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-714170.pdf
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EOKPQGV24RRBBI4TBZUDQMM4MEH7MXCY/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SIG7FZULMNK2XF6FZRU4VWYDQXNMUGAJ/
- https://logging.apache.org/log4j/2.x/security.html
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0032
- https://security.gentoo.org/glsa/202310-16
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-log4j-qRuKNEbd
- https://www.cve.org/CVERecord?id=CVE-2021-44228
- https://www.debian.org/security/2021/dsa-5022
- https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00646.html
- https://www.kb.cert.org/vuls/id/930724
- https://www.oracle.com/security-alerts/alert-cve-2021-44228.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-45046
- https://github.com/projectdiscovery/nuclei-templates/blob/main/dast/cves/2021/CVE-2021-45046.yaml
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- https://github.com/mergebase/log4j-samples