CVE-2026-33216

HIGH

NATS has MQTT plaintext password disclosure

Title source: cna
STIX 2.1

Description

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, for MQTT deployments using usercodes/passwords: MQTT passwords are incorrectly classified as a non-authenticating identity statement (JWT) and exposed via monitoring endpoints. Versions 2.11.14 and 2.12.6 contain a fix. As a workaround, ensure monitoring end-points are adequately secured. Best practice remains to not expose the monitoring endpoint to the Internet or other untrusted network users.

Scores

CVSS v3 8.6
EPSS 0.0005
EPSS Percentile 14.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-256
Status published
Products (5)
linuxfoundation/nats-server < 2.11.15
nats-io/nats-server 0Go
nats-io/nats-server 0 - 2.11.15Go
nats-io/nats-server < 2.11.15
nats-io/nats-server >= 2.12.0-RC.1, < 2.12.6
Published Mar 25, 2026
Tracked Since Mar 26, 2026