CVE-2026-33215
NATS is vulnerable to MQTT hijacking via Client ID
6.5
MEDIUM
CVSS 3.1
EPSS 0.02%
Description
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.
How to fix CVE-2026-33215
To remediate CVE-2026-33215, upgrade the affected package to a fixed version below.
- —upgrade to 2.11.15 or later
- —no fix listed
- —no fix listed
- —upgrade to 2.11.15 or later
- —upgrade to 2.11.15 or later
Is CVE-2026-33215 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (5)
- from 0, < 2.11.15, >= 2.12.0, < 2.12.6
- from 0
- from 0
- from 0, < 2.11.15
- from 0, < 2.11.15, >= 2.12.0-RC.1, < 2.12.6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L |