A critical authentication vulnerability in Apache Artemis and ActiveMQ Artemis allows unauthenticated remote attackers to hijack active sessions, posing a severe risk of total system compromise.

This is a missing authentication vulnerability (CWE-306) within the CORE protocol implementation. An unauthenticated attacker can send a specifically crafted SESSION_REATTACH packet to the service, enabling them to hijack an existing, authenticated session and perform actions with the privileges of that session.

The vulnerability carries a CVSS score of 9.8, indicating a critical severity level due to the potential for full unauthorized access to the messaging system. Successful exploitation allows an attacker to assume the identity of an authenticated user, which may result in data exfiltration, unauthorized administrative actions, or the disruption of critical business messaging services.

Immediate Action: Administrators must upgrade Apache Artemis to version 2.57.0 immediately, as this version contains the necessary security patches to prevent session hijacking.

Proactive Monitoring: Review access logs for suspicious or malformed CORE protocol packets and monitor for unusual session reattachment attempts that do not correlate with legitimate client behavior.

Compensating Controls: If immediate patching is not feasible, consider restricting network access to the Artemis messaging port to trusted IP ranges only to reduce the attack surface.

Public Exploit Available: No (exploit_available unknown).

Given the critical nature of this vulnerability and the ease with which an attacker can hijack sessions without authentication, organizations should prioritize the update to version 2.57.0. Failure to patch leaves the message broker susceptible to complete takeover, which could compromise the integrity and confidentiality of the entire messaging infrastructure.