CVE-2021-4104: Deserialization of Untrusted Data

December 14, 2021 (updated December 22, 2023)

JMSAppender in Log4j is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration. The attacker can provide TopicBindingName and TopicConnectionFactoryBindingName configurations causing JMSAppender to perform JNDI requests that result in remote code execution in a similar fashion to CVE-2021-44228. Note this issue only affects Log4j when specifically configured to use JMSAppender, which is not the default. Apache Log4j reached end of life in August Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.

References

access.redhat.com/security/cve/CVE-2021-4104
github.com/apache/logging-log4j2/pull/608
nvd.nist.gov/vuln/detail/CVE-2021-4104
www.cve.org/CVERecord?id=CVE-2021-44228
www.kb.cert.org/vuls/id/930724

Code Behaviors & Features

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