CVE-2021-4104
JMSAppender in Log4j 1.2 is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 80.6%, higher than 100% of all known CVEs. Patch or mitigate before the next change window.
Description
JMSAppender in Log4j 1.2 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 1.2 when specifically configured to use JMSAppender, which is not the default. Apache Log4j 1.2 reached end of life in August 2015. Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 80.60% probability · 100th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-502
- Affected
- apache/log4j · fedoraproject/fedora · redhat/codeready studio · redhat/integration camel k · redhat/integration camel quarkus · redhat/jboss a-mq · redhat/jboss a-mq streaming · redhat/jboss data grid · redhat/jboss data virtualization · redhat/jboss enterprise application platform · redhat/jboss fuse · redhat/jboss fuse service works · redhat/jboss operations network · redhat/jboss web server · redhat/openshift application runtimes · redhat/openshift container platform · redhat/process automation · redhat/single sign-on · redhat/software collections · redhat/enterprise linux · +26 more
- Source
- security@apache.org
EPSS 80.6% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2022/01/18/3
- https://access.redhat.com/security/cve/CVE-2021-4104
- https://github.com/apache/logging-log4j2/pull/608#issuecomment-990494126
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0033
- https://security.gentoo.org/glsa/202209-02
- https://security.gentoo.org/glsa/202310-16
- https://security.gentoo.org/glsa/202312-02
- https://security.gentoo.org/glsa/202312-04
- https://security.netapp.com/advisory/ntap-20211223-0007/
- https://www.cve.org/CVERecord?id=CVE-2021-44228
- https://www.kb.cert.org/vuls/id/930724
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
- http://www.openwall.com/lists/oss-security/2022/01/18/3
- https://access.redhat.com/security/cve/CVE-2021-4104
- https://github.com/apache/logging-log4j2/pull/608#issuecomment-990494126
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0033
- https://security.gentoo.org/glsa/202209-02
- https://security.gentoo.org/glsa/202310-16
- https://security.gentoo.org/glsa/202312-02
- https://security.gentoo.org/glsa/202312-04
- https://security.netapp.com/advisory/ntap-20211223-0007/
- https://www.cve.org/CVERecord?id=CVE-2021-44228
- https://www.kb.cert.org/vuls/id/930724
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.