CVE-2026-33216

Updated on 25 Mar 2026

Severity

8.6 High severity

Details

CVSS score
8.6
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Overview

About vulnerability

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.

Details