CVE-2026-50734: Apache ActiveMQ

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All. An unauthenticated network attacker can cause a broker DoS by sending a crafted WireFormatInfo frame with a malicious large size value. The value is not validate and causes the broker to attempt allocation during pre-auth negotiation which can trigger OOM and crash the broker. This issue affects Apache ActiveMQ Client: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6.2.7. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.

Affected products

• Apache ActiveMQ: before 5.19.8 (fixed in 5.19.8); from 6.0.0, before 6.2.7 (fixed in 6.2.7)

Published 2026-06-30. Last modified 2026-07-02.