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.
Affected products
linuxfoundation: nats-server
References8
- advisories.nats.io/CVE/secnote-2026-07.txt Vendor Advisory
- github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27… Vendor Advisory
- access.redhat.com/errata/RHSA-2026:21769
- access.redhat.com/errata/RHSA-2026:22347
- access.redhat.com/errata/RHSA-2026:23345
- access.redhat.com/security/cve/CVE-2026-33217
- bugzilla.redhat.com/show_bug.cgi?id=2451446
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33217…
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 19 · as of 12 November 2026
- CWE
- CWE-863CWE-425
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