# CVE-2026-50734: Apache ActiveMQ denial of service via excessive memory allocation

Source: https://junglewise.ai/threats/cve-2026-50734-apache-activemq-denial-of-service-via-excessive-memory-allocation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-30. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-50734 · Severity: high · CVSS 7.5 · Published 2026-06-30

Apache ActiveMQ is a popular open-source message broker used to facilitate communication between different software applications. A vulnerability in how it handles initial connection requests allows an unauthenticated attacker to crash the service by forcing it to exhaust its available memory. This results in a denial-of-service (DoS) condition, disrupting message delivery and business operations that rely on the broker.

Technologies: [Apache Software Foundation ActiveMQ All](https://junglewise.ai/threats/technologies/activemq-all), [Apache Software Foundation ActiveMQ Client](https://junglewise.ai/threats/technologies/activemq-client), [org.apache.activemq:activemq-all (Maven)](https://junglewise.ai/threats/technologies/org-apache-activemq-activemq-all), [org.apache.activemq:activemq-client (Maven)](https://junglewise.ai/threats/technologies/org-apache-activemq-activemq-client), [org.apache.activemq:apache-activemq (Maven)](https://junglewise.ai/threats/technologies/org-apache-activemq-apache-activemq). Vendors: [Apache Software Foundation](https://junglewise.ai/threats/vendors/apache-software-foundation), [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2026-50734 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-50734 being exploited in the wild.

**How severe is CVE-2026-50734?** High severity, with a CVSS score of 7.5, published 30 June 2026.

**Which products and versions are affected?** Apache Software Foundation ActiveMQ All before 5.19.8, 6.0.0 to 6.2.6; Apache Software Foundation ActiveMQ Client before 5.19.8, 6.0.0 to 6.2.6; org.apache.activemq:activemq-all (Maven) < 5.19.8, ECOSYSTEM:introduced=0,fixed=5.19.8; org.apache.activemq:activemq-client (Maven) < 5.19.8, ECOSYSTEM:introduced=0,fixed=5.19.8; and 1 more.

**Is there a fix for CVE-2026-50734?** Yes. org.apache.activemq:activemq-all (Maven): upgrade to 5.19.8 or later; org.apache.activemq:activemq-client (Maven): upgrade to 5.19.8 or later; org.apache.activemq:apache-activemq (Maven): upgrade to 5.19.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-50734 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-50734?** Check whether you run Apache Software Foundation ActiveMQ All, Apache Software Foundation ActiveMQ Client, org.apache.activemq:activemq-all (Maven) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- org.apache.activemq:activemq-all (Maven): upgrade to 5.19.8 or later

  ```sh
  # set org.apache.activemq:activemq-all to 5.19.8 in your pom.xml or build.gradle
  ```

- org.apache.activemq:activemq-client (Maven): upgrade to 5.19.8 or later

  ```sh
  # set org.apache.activemq:activemq-client to 5.19.8 in your pom.xml or build.gradle
  ```

- org.apache.activemq:apache-activemq (Maven): upgrade to 5.19.8 or later

  ```sh
  # set org.apache.activemq:apache-activemq to 5.19.8 in your pom.xml or build.gradle
  ```


## Technical details

A Memory Allocation with Excessive Size Value vulnerability (CWE-789) exists in the Apache ActiveMQ broker. The flaw is located in the handling of WireFormatInfo frames during the pre-authentication negotiation phase. An unauthenticated remote attacker can send a crafted frame containing a malicious, large size value that the broker fails to validate. This causes the broker to attempt a massive memory allocation, leading to an Out-of-Memory (OOM) error and a subsequent process crash. The issue is resolved in versions 5.19.8 and 6.2.7.

## Affected products

- Apache ActiveMQ Client before 5.19.8, 6.0.0 to 6.2.6
- Apache ActiveMQ before 5.19.8, 6.0.0 to 6.2.6
- Apache ActiveMQ All before 5.19.8, 6.0.0 to 6.2.6

## Identifiers

- CVE-2026-50734
- BIT-ACTIVEMQ-2026-50734
- GHSA-7259-vf48-52q3

## Timeline

- 2026-06-30: disclosed
- 2026-06-30: advisory

## References

- [https://repo.maven.apache.org/maven2](https://repo.maven.apache.org/maven2)
- [https://lists.apache.org/thread/nxso951fnvf72qf9m475mpz4yf931xk0](https://lists.apache.org/thread/nxso951fnvf72qf9m475mpz4yf931xk0)

## Related threats

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- [Apache ActiveMQ Denial of Service via Out of Memory](https://junglewise.ai/threats/cve-2026-50750-apache-activemq-denial-of-service-via-out-of-memory)