#VU125791 Improper Check or Handling of Exceptional Conditions in ActiveMQ - CVE-2026-39304
Published: April 10, 2026
Vulnerability identifier: #VU125791
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-39304
CWE-ID: CWE-703
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
ActiveMQ
ActiveMQ
Software vendor:
Apache Foundation
Apache Foundation
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper handling of TLSv1.3 KeyUpdate messages in ActiveMQ NIO SSL transports when processing client-triggered TLSv1.3 handshake KeyUpdates. A remote attacker can rapidly trigger KeyUpdate messages to cause a denial of service.
Only TLSv1.3 is vulnerable to out-of-memory exhaustion; earlier TLS versions may cause a connection hang instead.
Remediation
Install security update from vendor's website.