CVE-2026-54412

HIGH 8.2

MQTT-C Heap Out-of-Bounds Read and Integer Underflow in mqtt_unpack_publish_response()

CVSS Score

8.2

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-125 CWE-191
Vendor	liambindle
Product	mqtt-c
Published	Jun 14, 2026
Last Updated	Aug 10, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Affected Versions

LiamBindle / MQTT-C

0 ≤ 1.1.6

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/LiamBindle/MQTT-C github.com: https://github.com/LiamBindle/MQTT-C/blob/v1.1.6/src/mqtt.c#L1334 cwe.mitre.org: https://cwe.mitre.org/data/definitions/125.html cwe.mitre.org: https://cwe.mitre.org/data/definitions/191.html

Credits

Saidakbarxon Maxsudxonov