Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT vulnerable to Integer Overflow or Wraparound

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.4 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS

• CVE-2026-40046: 0.38% estimated exploitation activity in the next 30 days; percentile 31.50 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Integer Overflow or Wraparound vulnerability in Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT. The fix for "CVE-2025-66168: MQTT control packet remaining length field is not properly validated" was only applied to 5.19.2 (and future 5.19.x) releases but was missed for all 6.0.0+ versions. This issue affects Apache ActiveMQ: from 6.0.0 before 6.2.4; Apache ActiveMQ All: from 6.0.0 before 6.2.4; Apache ActiveMQ MQTT: from 6.0.0 before 6.2.4. Users are recommended to upgrade to version 6.2.4 or a 5.19.x version starting with 5.19.2 or later (currently latest is 5.19.5), which fixes the issue.

Published by the source

9 Apr 2026, 18:31 UTC

Last modified by the source

10 Apr 2026, 21:35 UTC

Source last checked

26 Oct 2026, 16:45 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-xvqc-pp94-fmpx

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# Patch Next advisory brief: CVE-2026-40046

Advisory: Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT vulnerable to Integer Overflow or Wraparound
IDs: CVE-2026-40046, GHSA-xvqc-pp94-fmpx
Record: https://patchnext.com/advisories/cve-2026-40046 (revision 1, source checked 26 Oct 2026, 16:45 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.apache.activemq:activemq-mqtt 6.2.4; org.apache.activemq:apache-activemq 6.2.4; org.apache.activemq:activemq-all 6.2.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.apache.activemq:activemq-mqtt: affected >= 6.0.0, < 6.2.4; fixed in 6.2.4
- Maven org.apache.activemq:apache-activemq: affected >= 6.0.0, < 6.2.4; fixed in 6.2.4
- Maven org.apache.activemq:activemq-all: affected >= 6.0.0, < 6.2.4; fixed in 6.2.4

## Suggested inspection (read-only)
- Maven org.apache.activemq:activemq-mqtt: check the installed version with your package manager.
- Maven org.apache.activemq:apache-activemq: check the installed version with your package manager.
- Maven org.apache.activemq:activemq-all: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.apache.activemq:activemq-mqtt, org.apache.activemq:apache-activemq, org.apache.activemq:activemq-all.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-xvqc-pp94-fmpx (GitHub-reviewed advisory GHSA-xvqc-pp94-fmpx lists affected ranges: Maven org.apache.activemq:apache-activemq >=6.0.0 =6.0.0 =6.0.0 <6.2.4)

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