CVE-2026-33215
NATS is vulnerable to MQTT hijacking via Client ID
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-287 CWE-488 |
| Vendor | nats-io |
| Product | nats-server |
| Published | Mar 24, 2026 |
| Last Updated | Mar 25, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
Low
Affected Versions
nats-io / nats-server
< 2.11.15 >= 2.12.0-RC.1, < 2.12.6