CVE-2026-33215

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://advisories.nats.io/CVE/secnote-2026-06.tx	Broken Link
https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879	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, 17:19

Type	Values Removed	Values Added
References	~~() https://advisories.nats.io/CVE/secnote-2026-06.tx -~~	() https://advisories.nats.io/CVE/secnote-2026-06.tx - Broken Link
References	~~() https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879 -~~	() https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879 - Vendor Advisory
CPE		cpe:2.3:a:linuxfoundation:nats-server::::::::
Summary		(es) NATS-Server es un servidor de alto rendimiento para NATS.io, un sistema de mensajería nativo de la nube y del borde. El nats-server proporciona una interfaz de cliente MQTT. Antes de las versiones 2.11.15 y 2.12.5, las sesiones y los mensajes pueden ser secuestrados mediante la malversación del ID de cliente MQTT. Las versiones 2.11.15 y 2.12.5 parchean el problema. No hay soluciones alternativas conocidas disponibles.
First Time		Linuxfoundation Linuxfoundation nats-server

24 Mar 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-24 21:16

Updated : 2026-03-26 17:19

NVD link : CVE-2026-33215

Mitre link : CVE-2026-33215

CVE.ORG link : CVE-2026-33215

JSON object : View

Products Affected

linuxfoundation

nats-server

CWE

CWE-287

Improper Authentication

CWE-488

Exposure of Data Element to Wrong Session

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