CVE-2026-33217

EUVD-2026-15966
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.1 HIGH
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
GitHub_MCNA
7.1 HIGH
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
linuxfoundationnats-server
𝑥
< 2.11.15
linuxfoundationnats-server
2.12.0 ≤
𝑥
< 2.12.6
𝑥
= Vulnerable software versions
Common Weakness Enumeration
References
https://advisories.nats.io/CVE/secnote-2026-07.txt
https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5