CVE-2026-33217

moderate-risk
Published 2026-03-25

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.

Do I need to act?

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0.03% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
7
CVSS 7.1/10 High
NETWORK / LOW complexity

Affected Products (1)

Affected Vendors

Linuxfoundation

References (2)

Vendor Advisory https://advisories.nats.io/CVE/secnote-2026-07.txt
Vendor Advisory https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5
30
/ 100
moderate-risk
Severity 25/34 · High
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal