Auth bypass in Linuxfoundation Nats-server
CVE-2026-33217
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 MQT…
Vulnerability class: Broken Access Control
EPSS: 0.003 (17.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N.
Affected products
- Linuxfoundation Nats-server
- Nats-io Nats-server — versions < 2.11.15, >= 2.12.0-RC.1, < 2.12.6
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-33217?
- CVE-2026-33217 is a high-severity vulnerability in Linuxfoundation Nats-server, classified under Incorrect Authorization. CVSS score: 7.1/10. Published 2026-03-25.
- How severe is CVE-2026-33217?
- High severity. CVSS v3 base score is 7.1 out of 10.