CVE-2026-54412: Liambindle Mqtt-C

High severity, CVSS 8.2. EPSS: 0.7% chance of exploitation in the next 30 days.

LiamBindle MQTT-C through version 1.1.6 contains a heap-based out-of-bounds read and integer underflow in the mqtt_unpack_publish_response function in src/mqtt.c that allows a remote unauthenticated attacker controlling an MQTT broker - or able to inject MQTT traffic into an unencrypted session - to crash a subscribed MQTT-C client and potentially disclose adjacent heap memory by sending a single crafted PUBLISH packet.

Affected products

• Liambindle Mqtt-C: up to and including 1.1.6

Published 2026-06-14. Last modified 2026-08-10.