cve.bz

CVE-2026-39304

7.5 highEPSS 0.9%

Denial of Service via Out of Memory vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ. ActiveMQ NIO SSL transports do not correctly handle TLSv1.3 handshake KeyUpdates triggered by clients. This makes it possible for a client to rapidly trigger updates which causes the broker to exhaust all its memory in the SSL engine leading to DoS. Note: TLS versions before TLSv1.3 (such as TLSv1.2) are broken but are not vulnerable to OOM. Previous TLS versions require a full handshake renegotiation which causes a connection to hang but not OOM. This is fixed as well. This issue affects Apache ActiveMQ Client: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ Broker: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ: before 5.19.4, from 6.0.0 before 6.2.4. Users are recommended to upgrade to version 6.2.4 or 5.19.5, which fixes the issue.

CVSS 3.1
7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.9% chance of exploitation in the next 30 days; higher than 59% of CVEs (scores of 2026-10-26)
CWEs
CWE-400, CWE-770
Published
Modified
Record from
the NVD, synced

Affected

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-client<5.19.45.19.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-client>=6.0.0 <6.2.46.2.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-broker<5.19.45.19.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-broker>=6.0.0 <6.2.46.2.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-all<5.19.45.19.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:activemq-all>=6.0.0 <6.2.46.2.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:apache-activemq<5.19.45.19.4
GHSA-5568-6qcg-g7fxMavenorg.apache.activemq:apache-activemq>=6.0.0 <6.2.46.2.4

References

Check your stackJSON