GitHub Advisoryadvisory · Go

GHSA-v722-jcv5-w7mc NATS has MQTT plaintext password disclosure

HIGH Published 2026-03-24 Modified 2026-03-27 Official page ↗
Aliases
CVE-2026-33216
Ecosystem
Go
Packages
github.com/nats-io/nats-server/v2, github.com/nats-io/nats-server
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Weaknesses
CWE-256
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 • Go github.com/nats-io/nats-server: all versions (no fix yet)

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 For MQTT deployments using usercodes/passwords: MQTT passwords are incorrectly classified as a non-authenticating identity statement (JWT) and exposed via monitoring endpoints. Affected Versions Any version before v2.12.6 or v2.11.15 Workarounds Ensure monitoring end-points are adequately secured. Best practice remains to not expose the monitoring endpoint to the Internet or other untrusted network users.

Related

Alias · CVE (1)

  • CVE-2026-33216 NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. vulnerability

Weakness · CWE (1)

  • CWE-256 Plaintext Storage of a Password weakness

References