A flaw was found in Apache ActiveMQ Artemis. The JsonUtil.fromJsonArray() method uses ObjectInputStream.readObject() to deserialize CompositeData from Base64-encoded serialized objects in management message bodies sent to the activemq.management address. While the deserialization is protected by an allowlist (java.util,java.lang,javax.management) that blocks RCE gadget chains, an authenticated attacker with the MANAGE role can craft a deserialization bomb using deeply nested java.util.HashSet/HashMap structures to exhaust CPU/memory and crash the broker JVM, causing denial of service for all connected clients.

When the broker is processing message-based management requests, sent by an authenticated messaging client that is authorized with MANAGE permission to perform management-via-messaging, the parameter processing can trigger Java deserialization of certain method parameters that the broker will not utilise. The permitted types allow to craft a payload causing excessive computation and pinning the processing thread, leading to denial of service. This issue affects Apache Artemis: from 2.50.0 through 2.56.0; Apache ActiveMQ Artemis: from 1.3.0 through 2.44.0. Users are recommended to upgrade to version 2.57.0, which fixes the issue.

When the broker is processing message-based management requests, sent by an authenticated messaging client that is authorized with MANAGE permission to perform management-via-messaging, the parameter processing can trigger Java deserialization of certain method parameters that the broker will not utilise. The permitted types allow to craft a payload causing excessive computation and pinning the processing thread, leading to denial of service. This issue affects Apache Artemis: from 2.50.0 through 2.56.0; Apache ActiveMQ Artemis: from 1.3.0 through 2.44.0. Users are recommended to upgrade to version 2.57.0, which fixes the issue.