Apache ActiveMQ - Remote Code Execution via HTTP Discovery Transport Bypass
Description
Apache ActiveMQ before 5.19.6 and 6.0.0 through 6.2.4 is vulnerable to remote code execution via a bypass of the CVE-2026-34197 security fix. The original fix blocked the "vm://" transport scheme in BrokerView.addNetworkConnector() and BrokerView.addConnector() to prevent authenticated attackers from loading malicious Spring XML configurations via the Jolokia API. However, the fix only denied the "vm" scheme. An attacker can bypass this restriction by using the HTTP Discovery transport(http://attacker/discovery), which is not in the denied scheme list. The attacker-controlled HTTP endpoint returns a vm:// transport URI as a second-stage response, which then loads a remote Spring XML application context, leading to arbitrary code execution on the broker JVM. The activemq-http module must be on the classpath (present by default in the "all" distribution), and authenticated access to the Jolokia API (/api/jolokia/) is required.
Severity
CVSS Score
8.8
Exploit Probability
4%
Affected Product
activemq