VulnerabilityAnalyzed

CVE-2026-33215

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system.

MEDIUM 6.5EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.

CVSS 3.1: 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS: 0.24% probability · 15th percentile
CISA KEV: Not listed
Weakness: CWE-287, CWE-488
Affected: linuxfoundation/nats-server
Source: security-advisories@github.com

References

https://advisories.nats.io/CVE/secnote-2026-06.txBroken Link
https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.