CVE-2026-111821
Apache ActiveMQ, Apache ActiveMQ KahaDB: Oversized client identifier strings poison the KahaDB journal
Improper input validation vulnerability in Apache ActiveMQ, Apache ActiveMQ KahaDB. A user can create a durable subscription with a clientId and subscription name that have a combined length > 65,535 (while separately being shorter) on a broker using KahaDB which can cause the broker to shutdown and be unrecoverable. This issue affects Apache ActiveMQ: from 6.0.0 before 6.3.3, before 5.19.12; Apache ActiveMQ KahaDB: from 6.0.0 before 6.3.3, before 5.19.12. Users are recommended to upgrade to version 6.4.0, 6.3.3 or 5.19.12, which fixes the issue.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Apache ActiveMQ Apache Software Foundation org.apache.activemq:apache-activemq
maven |
≥ 6.0.0; < 6.3.3 (affected, semver) ≥ 0; < 5.19.12 (affected, semver) Other versions: unaffected |
CNA: apache |
| Apache ActiveMQ KahaDB Apache Software Foundation org.apache.activemq:activemq-kahadb-store
maven |
≥ 6.0.0; < 6.3.3 (affected, semver) ≥ 0; < 5.19.12 (affected, semver) Other versions: unaffected |
CNA: apache |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
No CVSS assessment reported. An unscored record is not a low-severity determination.
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://lists.apache.org/thread/p8gxq66lmztkrls74wkz3xh9chqd0pwlCNA: apache · vendor-advisory
- http://www.openwall.com/lists/oss-security/2026/11/03/19ADP: CVE
- https://lists.apache.org/thread/p8gxq66lmztkrls74wkz3xh9chqd0pwl[email protected]
- http://www.openwall.com/lists/oss-security/2026/11/03/19af854a3a-2127-422b-91ae-364da2661108
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