GHSA-fcjp-h8cc-6879
NATS is vulnerable to MQTT hijacking via Client ID
At a glance
- Published
- Updated
- CVE
- CVE-2026-33215
- Aliases
- BIT-nats-2026-33215, GO-2026-4833
- CVSS_V3
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L
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 packages
| Package | Versions |
|---|---|
| Go · github.com/nats-io/nats-server/v2 | introduced 0, fixed 2.11.15 |
| Go · github.com/nats-io/nats-server/v2 | introduced 2.12.0-RC.1, fixed 2.12.6 |
References
- https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879 WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-33215 ADVISORY
- https://advisories.nats.io/CVE/secnote-2026-06.tx WEB
- https://github.com/nats-io/nats-server PACKAGE
- https://pkg.go.dev/vuln/GO-2026-4833 WEB
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |