Executive brief
Apache ActiveMQ is a popular open-source message broker used to facilitate communication between different software applications. A security flaw allows a user with low-level access to bypass security rules and send unauthorized messages to restricted data queues. This could allow an attacker to inject malicious data or disrupt business operations by interacting with protected message streams they should not have access to.
Technical details
An improper authorization vulnerability exists in Apache ActiveMQ's handling of temporary composite destinations. An authenticated attacker with low privileges can bypass per-destination write ACLs by sending messages to a temporary composite destination whose physical name contains a comma-separated list of legitimate, restricted queues. Because the broker marks the destination as 'temporary', it incorrectly skips standard authorization checks, allowing the attacker to publish messages to any queue in the composite list. This affects ActiveMQ Broker, ActiveMQ All, and the main ActiveMQ distribution across versions 5.x and 6.x. Users should upgrade to 5.19.9, 6.2.8, or 6.3.0 to resolve the issue.
Affected products
- Apache ActiveMQ Broker < 5.19.9, 6.0.0 to < 6.2.8
- Apache ActiveMQ All < 5.19.9, 6.0.0 to < 6.2.8
- Apache ActiveMQ < 5.19.9, 6.0.0 to < 6.2.8
Timeline
- 2026-07-27: disclosed: Initial disclosure on oss-security mailing list
- 2026-07-28: advisory: NVD publication date