Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All. (CVE-2026-50734)
Description
CVE-2026-50734 is a vulnerability in Apache ActiveMQ and its client where an unauthenticated network attacker can cause a denial of service by sending a crafted WireFormatInfo frame with an excessively large size value. This triggers an out-of-memory condition during pre-authentication negotiation, crashing the broker. The issue affects versions before 5.19.8 and from 6.0.0 before 6.2.7. Upgrading to versions 5.19.8 or 6.2.7 or later mitigates the vulnerability.
CVSS v3.1
Score 7.5high
Affected software
pkg:deb/ubuntu/activemq?arch=source&distro=esm-apps/xenialpkg:deb/ubuntu/activemq?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/activemq?arch=source&distro=esm-apps/focalpkg:deb/ubuntu/activemq?arch=source&distro=esm-apps/jammypkg:deb/ubuntu/activemq?arch=source&distro=noblepkg:deb/ubuntu/activemq?arch=source&distro=questingpkg:deb/ubuntu/activemq?arch=source&distro=stonkingpkg:deb/ubuntu/activemq?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-50734 in Apache ActiveMQ and Apache ActiveMQ Client arises from improper validation of the size value in the WireFormatInfo frame. An unauthenticated attacker can send a frame with a maliciously large size value, causing the broker to attempt excessive memory allocation during the pre-authentication negotiation phase. This can lead to an out-of-memory (OOM) condition and crash the broker, resulting in a denial of service (DoS). The flaw affects Apache ActiveMQ Client and Apache ActiveMQ versions prior to 5.19.8 and versions from 6.0.0 up to but not including 6.2.7. The vendor has fixed the issue in versions 5.19.8 and 6.2.7.
Potential Impact
An unauthenticated remote attacker can cause a denial of service by crashing the Apache ActiveMQ broker through excessive memory allocation triggered by a crafted WireFormatInfo frame. There is no impact on confidentiality or integrity reported. The impact is limited to availability disruption.
Mitigation Recommendations
Users should upgrade Apache ActiveMQ and Apache ActiveMQ Client to version 5.19.8 or 6.2.7 or later, where this vulnerability is fixed. No other mitigations are specified. Patch status is confirmed as fixed in these versions.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-50734
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:Pro:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:25.10","Ubuntu:26.10","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ad3f60a2cdf04f6566640f2
Added to database: 10/17/2026, 22:26:18 UTC
Last enriched: 10/18/2026, 00:56:58 UTC
Last updated: 10/18/2026, 00:56:58 UTC
Views: 4
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