High
activemq — security advisory
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.
- Products
- activemq
- Affected versions
- 5.13.2+dfsg-2, 5.13.2+dfsg-2ubuntu0.1~esm1, 5.14.5-3, 5.15.10-1, 5.15.11-1, 5.15.11-1ubuntu0.1~esm1, 5.15.2-2, 5.15.3-2, 5.15.8-2~18.04, 5.15.8-2~18.04.1~esm1, 5.16.1-1, 5.16.1-1ubuntu0.1, 5.16.1-1ubuntu0.1~esm1, 5.17.2+dfsg-2, 5.17.6+dfsg-1, 5.17.6+dfsg-2, 5.17.6+dfsg-2ubuntu1, 5.6.0+dfsg1-4+deb8u1ubuntu1, 5.6.0+dfsg1-5
- Fixed versions
- Not specified
- CVEs
- CVE-2026-39304
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:02 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-39304
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
activemq
Fixed versions: Not specified
Complete source record
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"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-39304",
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"modified": "2026-10-17T13:00:03.837219445Z",
"provider": "osv",
"upstream": [
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"references": [
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"https://www.openwall.com/lists/oss-security/2026/04/09/17"
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"published_at": "2026-04-10T11:16:00+00:00"
}