High 7.5Published Apr 10, 2026

CVE-2026-39304Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ: Incorrect handling of TLSv1.3 KeyUpdate can be exploited to cause DoS via OOM

Updated under an hour ago (Oct 27, 2026, 7:50 AM ET)

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It affects Apache Software Foundation Apache ActiveMQ Client and 12 other products. Add what you run to find out whether that includes you.

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Every CVE for Apache Software Foundation Apache ActiveMQ Client

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-400, CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: apache
NVD analysis: Modified
Record last updated: Jul 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Apache Software Foundation Apache ActiveMQ Client apache_software_foundation:apache_activemq_client (from the name)	before 5.19.4; from 6.0.0 before 6.2.4	CNA record
Apache Software Foundation Apache ActiveMQ Broker apache_software_foundation:apache_activemq_broker (from the name)	before 5.19.4; from 6.0.0 before 6.2.4	CNA record
Apache Software Foundation Apache ActiveMQ All apache_software_foundation:apache_activemq_all (from the name)	before 5.19.4; from 6.0.0 before 6.2.4	CNA record
Apache Software Foundation Apache ActiveMQ apache_software_foundation:apache_activemq (from the name)	before 5.19.4; from 6.0.0 before 6.2.4	CNA record
Red Hat Red Hat AMQ Broker 7 redhat:amq_broker	7	CISA ADP
Red Hat Red Hat build of Apache Camel for Spring Boot 4 redhat:camel_spring_boot	4	CISA ADP
Red Hat Red Hat Data Grid 8 redhat:jboss_data_grid	8	CISA ADP
Red Hat Red Hat Enterprise Linux 8 redhat:enterprise_linux	8	CISA ADP
Red Hat Red Hat Fuse 7 redhat:jboss_fuse	7	CISA ADP
Red Hat Red Hat JBoss Enterprise Application Platform 7 redhat:jboss_enterprise_application_platform	7	CISA ADP
1–10 of 13

References

References

https://activemq.apache.org/security-advisories.data/CVE-2026-39304-announcement.txt	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/04/09/17	mailing-list, third-party-advisory
https://access.redhat.com/security/cve/CVE-2026-39304
https://bugzilla.redhat.com/show_bug.cgi?id=2457275
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39304.json

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.