Apache ActiveMQ: Denial of Service via Out of Memory vulnerability
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.
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Java / Kotlin (Maven) | org.apache.activemq:activemq-all | < 5.19.4, >= 6.0.0, < 6.2.4 | 5.19.4, 6.2.4 |
| Java / Kotlin (Maven) | org.apache.activemq:activemq-broker | < 5.19.4, >= 6.0.0, < 6.2.4 | 5.19.4, 6.2.4 |
| Java / Kotlin (Maven) | org.apache.activemq:activemq-client | < 5.19.4, >= 6.0.0, < 6.2.4 | 5.19.4, 6.2.4 |
| Java / Kotlin (Maven) | org.apache.activemq:apache-activemq | < 5.19.4, >= 6.0.0, < 6.2.4 | 5.19.4, 6.2.4 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-400- Platform
- Java / Kotlin (Maven)
- Package
org.apache.activemq:activemq-all, org.apache.activemq:activemq-broker, org.apache.activemq:activemq-client- Disclosed
- 10.04.2026
- Updated
- 11.10.2026 13:20
Sources and licenses
OSV / GitHub Advisory Database - GHSA-5568-6qcg-g7fx - CC BY 4.0
Vulnerability history: org.apache.activemq:activemq-client
All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 18
- First → latest
- 10.2018 04.2026
- Without a fix
- 0
- Exploited in attacks
- 2
Severity breakdown
- Critical 4
- High 4
- Medium 10
Disclosures per year
- 2018: 1
- 2019: 2
- 2020: 0
- 2021: 0
- 2022: 11
- 2023: 1
- 2024: 0
- 2025: 1
- 2026: 2
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Apache ActiveMQ: Denial of Service via Out of Memory vulnerability this entry
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