GHSA-fcjp-h8cc-6879MediumCVSS 6.5
NATS is vulnerable to MQTT hijacking via Client ID
🔗 CVE IDs covered (1)
📋 Description
Background
NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.
The nats-server provides an MQTT client interface.
Problem Description
Sessions and Messages can by hijacked via MQTT Client ID malfeasance.
Affected Versions
Any version before v2.12.6 or v2.11.15
Workarounds
None.
Resources
- This document is canonically: https://advisories.nats.io/CVE/secnote-2026-06.txt
- GHSA advisory: https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879
- MITRE CVE entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33215
🎯 Affected products2
- go/github.com/nats-io/nats-server/v2:< 2.11.15
- go/github.com/nats-io/nats-server/v2:>= 2.12.0-RC.1, < 2.12.6