CVE-2026-40046CWE-190

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

High · published April 9, 2026

CVSS v3.1
7.5
EPSS
1%
Percentile
48.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00609 · 48.5th percentile
Weakness
CWE-190 · Integer Overflow or Wraparound
Published
2026-04-09T15:58Z
EPSS history
Timeline
  • 09 APR 15:58Z
    Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ MQTT: Missing fix for CVE-2025-66168: MQTT control packet remaining length field is not properly validated
    cvelistv5