Integer Overflow or Wraparound Affecting org.apache.activemq:activemq-mqtt package, versions [,5.19.2)[6.0.0,6.2.4)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published5 Mar 2026
- disclosed4 Mar 2026
- creditGai Tanaka
Introduced: 4 Mar 2026
CVE-2025-66168 (opens in a new tab)How to fix?
Upgrade org.apache.activemq:activemq-mqtt to version 5.19.2, 6.2.4 or higher.
Overview
Affected versions of this package are vulnerable to Integer Overflow or Wraparound when decoding malformed MQTT packets, due to improper validation of the Remaining Length. An attacker can cause the broker to misinterpret payloads as multiple MQTT control packets by sending malicious packets.
Note:
This is only exploitable if the MQTT transport connector is enabled.
This issue got CVE-2026-40046 assigned specifically to track backports to 6.x.x version line.