GitHub Advisoryadvisory · Go

GHSA-fcjp-h8cc-6879 NATS is vulnerable to MQTT hijacking via Client ID

MEDIUM Published 2026-03-24 Modified 2026-03-27 Official page ↗
Aliases
CVE-2026-33215
Ecosystem
Go
Packages
github.com/nats-io/nats-server/v2
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L
Weaknesses
CWE-287
Reviewed
2026-03-24

Affected packages

• Go github.com/nats-io/nats-server/v2: < 2.11.15 → fixed in 2.11.15 • Go github.com/nats-io/nats-server/v2: >= 2.12.0-RC.1, < 2.12.6 → fixed in 2.12.6

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: • GHSA advisory: • MITRE CVE entry:

Related

Alias · CVE (1)

  • CVE-2026-33215 NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. vulnerability

Weakness · CWE (1)

  • CWE-287 Improper Authentication weakness

References