CVE-2026-40046

Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT: Missing fix for CVE-2025-66168: MQTT control packet remaining length field is not properly validated

Description

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.

Scores

Weaknesses (CWE)

• CWE-190

Advisories

• GHSA-xvqc-pp94-fmpx — Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT vulnerable to Integer Overflow or Wraparound

European references

• ENISA EUVD · EUVD-2026-20956
• GCVE · GCVE-0-2026-40046

CERT-FR advisories

• CERTFR-2026-AVI-1094 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
• CERTFR-2026-AVI-0958 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
• CERTFR-2026-AVI-0933 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected products

References

• https://www.cve.org/CVERecord?id=CVE-2025-66168
• https://activemq.apache.org/security-advisories.data/CVE-2026-40046-announcement.txt
• https://lists.apache.org/thread/zdntj5rcgjjzrpow84o339lzldy68zrg

Sources