CRITICALFixed upstream

CVE-2026-57967

Apache Artemis CORE protocol session reattachment lets an unauthenticated attacker take over a session

Technology

ActiveMQ Artemis

CVSS Score

9.8 / 10.0

Affected Versions

Apache Artemis 2.50.0 to 2.56.0; Apache ActiveMQ Artemis 1.0.0 to 2.44.0

Upstream Fix

2.57.0

Published

September 10, 2026

OSSeva Coverage

Fixed upstream

Description

An unauthenticated remote attacker can craft a CORE protocol SESSION_REATTACH packet to steal an existing session and carry on as the user who authenticated it. Apache rates the issue important; the 9.8 score on NVD is from CISA-ADP.

Upstream record: NVD · CVE.org

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If you're running Apache Artemis 2.50.0 to 2.56.0; Apache ActiveMQ Artemis 1.0.0 to 2.44.0, you need this patch. Book a discovery call to get covered.

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