NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client…
GitHub_M·CWE-287·Published 2026-03-24
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.
NATS is vulnerable to MQTT hijacking via Client ID in github.com/nats-io/nats-server
### 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>
NATS-Server es un servidor de alto rendimiento para NATS.io, un sistema de mensajería nativo de la nube y del borde. El nats-server proporciona una interfaz de cliente MQTT. Antes de las versiones 2.11.15 y 2.12.5, las sesiones y los mensajes pueden ser secuestrados mediante la malversación del ID de cliente MQTT. Las versiones 2.11.15 y 2.12.5 parchean el problema. No hay soluciones alternativas conocidas disponibles.
| Version | Type | Source | Base | Exp | Impact | Vector |
|---|---|---|---|---|---|---|
| 3.1 | Primary | cve.org | 6.5 | — | — | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L |
| 3.1 | Primary | cve.org | 6.5 | — | — | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L |
| 3.1 | Primary | NVD | 6.5 | 3.9 | 2.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| 3.1 | Secondary | GHSA | 6.5 | — | — | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L |
| 3.1 | Secondary | NVD | 6.5 | 2.2 | 4.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L |