Mavenlog4j:
No fixed version published. Check the advisory or remove the package.
Affected versions
| If you run | Upgrade to |
|---|---|
| 1.2.0 through 1.2.17 | No fix published |
CVE-2021-4104 Public exploit High · 7.5 EPSS 80.6%
Deserialization of untrusted data in JMSAppender in Apache Log4j 1.2
Apache Software Foundation · Apache Log4j 1.x
Summary
The flaw is a deserialization of untrusted data issue in the JMSAppender component of Apache Log4j 1.x (1.2 line). It affects only deployments that have been specifically configured to use JMSAppender, which is not the default. An attacker who already has write access to the Log4j configuration can supply TopicBindingName and TopicConnectionFactoryBindingName values that cause JMSAppender to make JNDI requests, enabling remote code execution. The attack requires network access, low privileges (write access to the configuration), and a high-complexity condition, with no user interaction needed.
Official description · CVE.org
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.
Priority scorePatchfirst’s 0 to 100 ranking. It adds points for CISA KEV listing, ransomware use, EPSS, threat reports, public exploit code and CVSS. Every CVE page shows the breakdown. Breakdown
68.1 / 100
- Exploited
- Yes, in VulnCheck KEV
- Reports
- 0
- Tactics
- 0/15
Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 4 months after disclosure. Public exploit code (PoC-in-GitHub) was available the same day.
- First seen exploitedVulnCheck KEV evidence+4 mo
Patch historyEarlier and later CVEs in the same code, in date order. It shows when a fix was bypassed or incomplete and which version finally fixed it.
See the family treeA fix was bypassed or incomplete 2 times over 8 months.
Same bug familyLinked by evidence that a fix failed or the same code was patched again. Oldest first.
relatedHigh
Why these are linked: Link confidenceHow strong the evidence is that two CVEs are related. High: stated in the CVE text or linked in an advisory, or the same code was patched one release apart. Medium: the same code, or a version step plus a similar description. Low: similar description only.
- Linked in OSV/GitHub advisoryGHSA-fp5r-v3w9-4333
This CVECVE-2021-4104Deserialization of untrusted data in JMSAppender in Apache Log4j…14 Dec 2021- same family
incomplete fixHigh
Why these are linked: Link confidenceHow strong the evidence is that two CVEs are related. High: stated in the CVE text or linked in an advisory, or the same code was patched one release apart. Medium: the same code, or a version step plus a similar description. Low: similar description only.
- Stated in the CVE text
It was found that the original fix for log4j CVE-2021-44228 and CVE-2021-45046 in the OpenShift metering hive containers was incomplete, as not all JndiLookup.class files were removed.
- Stated in the CVE text
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
No techniques linkedNo ATT&CK techniques are linked to this CVE yet. MITRE CTID has not mapped it, and no report passage in the corpus ties it to a technique.
Am I affected? What do I upgrade to?
From GitHub Security Advisories and OSV2 packages in 1 ecosystem. Main package: log4j:log4j.
Other packages that bundle this code (1)
Forks, repackagings and products that include the affected code. Each has its own fixed version.
- Mavenorg.zenframework.z8.dependencies.commons:log4j-1.2.17Affected: 2.0 and earlierNo fixed version published
What security researchers reported
Not named in any threat report yetAlso mentioned in 18 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
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