PT-2026-27519 · Nats.Io · Nats Server

Published 2026-03-24 · Updated 2026-03-24 · CVE-2026-33215

Mitre

CVSS v3.1

6.5

Medium

AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L

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.

Fix

Improper Authentication

Weakness Enumeration

CWE-287

CWE-488

Related Identifiers

CVE-2026-33215

Affected Products

Nats Server

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-33215 · Security Note
• https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879 · Note
• https://advisories.nats.io/CVE/secnote-2026-06.tx · Note