CVE-2026-40466: Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ: Possible bypass of CVE-2026-34197 via HTTP discovery second-stage URI
Improper Input Validation, Improper Control of Generation of Code ('Code Injection') vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ.
An authenticated attacker may bypass the fix in CVE-2026-34197 by adding a connector using an HTTP Discovery transport via BrokerView.addNetworkConnector or BrokerView.addConnector through Jolokia if the activemq-http module is on the classpath. A malicious HTTP endpoint can return a VM transport through the HTTP URI which will bypass the validation added in CVE-2026-34197. The attacker can then use the VM transport's brokerConfig parameter to load a remote Spring XML application context using ResourceXmlApplicationContext. Because Spring's ResourceXmlApplicationContext instantiates all singleton beans before the BrokerService validates the configuration, arbitrary code execution occurs on the broker's JVM through bean factory methods such as Runtime.exec().
This issue affects Apache ActiveMQ Broker: before 5.19.6, from 6.0.0 before 6.2.5; Apache ActiveMQ All: before 5.19.6, from 6.0.0 before 6.2.5; Apache ActiveMQ: before 5.19.6, from 6.0.0 before 6.2.5.
Users are recommended to upgrade to version 5.19.6 or 6.2.5, which fixes the issue.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Apache ActiveMQ Brokerto a version that resolves this vulnerability.Fixed in 5.19.6 - Upgrade
Upgrade
Apache ActiveMQ Brokerto a version that resolves this vulnerability.Fixed in 6.2.5 - Upgrade
Upgrade
Apache ActiveMQ Allto a version that resolves this vulnerability.Fixed in 5.19.6 - Upgrade
Upgrade
Apache ActiveMQ Allto a version that resolves this vulnerability.Fixed in 6.2.5 - Upgrade
Upgrade
Apache ActiveMQto a version that resolves this vulnerability.Fixed in 5.19.6 - Upgrade
Upgrade
Apache ActiveMQto a version that resolves this vulnerability.Fixed in 6.2.5
Event History
Frequently Asked Questions
What is the severity of CVE-2026-40466?
CVE-2026-40466 is classified as a critical severity vulnerability due to its potential for code injection and improper input validation.
How do I fix CVE-2026-40466?
To fix CVE-2026-40466, update Apache ActiveMQ Broker or Apache ActiveMQ All to versions beyond 5.19.6 or versions between 6.0.0 and 6.2.5 exclusively.
What versions of Apache ActiveMQ are affected by CVE-2026-40466?
CVE-2026-40466 affects Apache ActiveMQ Broker and ActiveMQ All versions up to 5.19.6 and versions between 6.0.0 and 6.2.5.
What does CVE-2026-40466 exploit?
CVE-2026-40466 exploits insufficient input validation allowing for a possible bypass of previously remedied vulnerabilities.
Is it safe to use Apache ActiveMQ versions affected by CVE-2026-40466?
It is not safe to use affected versions of Apache ActiveMQ as they may be susceptible to exploitation through code injection.