Review reviewHigh

CVE-2026-50734

Apache Software Foundation Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All. An unauthenticated network attacker can cause a broker DoS by sending a crafted WireFormatInfo frame with a malicious large size value. The value is not validate and causes the broker to attempt allocation during pre-auth negotiation which can trigger OOM and crash the broker. This issue affects Apache ActiveMQ Client: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6....

CVSS: 7.5
EPSS: 0.54%
CISA KEV: Not listed
Published: 2026.06.30

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.54%

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: Apache Software Foundation Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All
Affected versions: 6.0.0, < 5.19.8, >= 6.0.0 < 6.2.7
Fixed versions: 5.19.8, 6.2.7

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Apache Software Foundation Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-789