CVE-2026-33217
Publication date 27 March 2026
Last updated 27 March 2026
Ubuntu priority
Description
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, when using ACLs on message subjects, these ACLs were not applied in the `$MQTT.>` namespace, allowing MQTT clients to bypass ACL checks for MQTT subjects. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| nats-server | 25.10 questing |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy | Not in release |
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
7.1 · High
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | High |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N |