CVE-2026-33216

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.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://advisories.nats.io/CVE/secnote-2026-05.txt	Mitigation Vendor Advisory
https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099	Patch
https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mc	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:linuxfoundation:nats-server::::::::
	cpe:2.3:a:linuxfoundation:nats-server::::::::

History

26 Mar 2026, 17:14

Type	Values Removed	Values Added
CPE		cpe:2.3:a:linuxfoundation:nats-server::::::::
First Time		Linuxfoundation Linuxfoundation nats-server
References	~~() https://advisories.nats.io/CVE/secnote-2026-05.txt -~~	() https://advisories.nats.io/CVE/secnote-2026-05.txt - Mitigation, Vendor Advisory
References	~~() https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099 -~~	() https://github.com/nats-io/nats-server/commit/b5b63cfc35a57075e09c1f57503d31721bed8099 - Patch
References	~~() https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mc -~~	() https://github.com/nats-io/nats-server/security/advisories/GHSA-v722-jcv5-w7mc - Mitigation, Vendor Advisory

25 Mar 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-25 20:16

Updated : 2026-03-26 17:14

NVD link : CVE-2026-33216

Mitre link : CVE-2026-33216

CVE.ORG link : CVE-2026-33216

JSON object : View

Products Affected

linuxfoundation

nats-server

CWE

CWE-256

Plaintext Storage of a Password

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