Description
Improper validation and restriction of a classpath path name vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ Web, Apache ActiveMQ. In two instances (when creating a Stomp consumer and also browsing messages in the Web console) an authenticated user provided "key" value could be constructed to traverse the classpath due to path concatenation. As a result, the application is exposed to a classpath path resource loading vulnerability that could potentially be chained together with another attack to lead to exploit. This issue affects Apache ActiveMQ Client: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ Broker: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ All: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ Web: before 5.19.3, from 6.0.0 before 6.2.2; Apache ActiveMQ: before 5.19.3, from 6.0.0 before 6.2.2. Users are recommended to upgrade to version 5.19.4 or 6.2.3, which fixes the issue. Note: 5.19.3 and 6.2.2 also fix this issue, but that is limited to non-Windows environments due to a path separator resolution bug fixed in 5.19.4 and 6.2.3.
Affected products
apache: activemq; apache: activemq broker; apache: activemq web
References2
- activemq.apache.org/security-advisories.data/CVE-2026-33227-ann… Vendor Advisory
- www.openwall.com/lists/oss-security/2026/04/06/4 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 12 November 2026
- CWE
- CWE-22
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