Executive brief
Apache Artemis is a widely-used open-source message broker that handles enterprise messaging for business applications. An unauthenticated attacker on the network can exploit a flaw in the CORE protocol to hijack an existing authenticated session, effectively taking over an active client connection and gaining unauthorized access to the message broker's functionality and data.
Technical details
The vulnerability is a session hijacking / authentication bypass in Apache Artemis's CORE protocol implementation. An unauthenticated remote attacker can craft a malicious SESSION_REATTACH packet to steal and assume control of an existing authenticated session. The attack requires network access to the CORE protocol port but no prior authentication credentials. Once exploited, the attacker gains full execution privileges of the compromised session, allowing them to perform any action the hijacked authenticated client is authorized to perform. Upgrade to Apache Artemis 2.57.0 or Apache ActiveMQ Artemis 2.45.0 or later to remediate.
Affected products
- Apache Artemis 2.50.0 through 2.56.0
- Apache ActiveMQ Artemis 1.0.0 through 2.44.0
Timeline
- 2026-09-10: disclosed: CVE-2026-57967 published
- 2026-09-10: patched: Fix available in Apache Artemis 2.57.0 and ActiveMQ Artemis 2.45.0