CVE-2026-8686

Missing bounds validation in the MQTT v5.0 property parser in coreMQTT before 5.0.1 allows an MQTT broker to cause a denial of service by sending a crafted packet. To remediate this issue, users should upgrade to v5.0.1.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-032-aws/	Vendor Advisory
https://github.com/FreeRTOS/coreMQTT/releases/tag/v5.0.1	Release Notes
https://github.com/FreeRTOS/coreMQTT/security/advisories/GHSA-6qh9-r6jp-2wxc	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freertos:coremqtt:5.0.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-15 19:17

Updated : 2026-06-17 11:04

NVD link : CVE-2026-8686

Mitre link : CVE-2026-8686

CVE.ORG link : CVE-2026-8686

JSON object : View

Products Affected

freertos

coremqtt

CWE

CWE-125

Out-of-bounds Read

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