CVE-2026-33223 MEDIUM

CVE-2026-33223: NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing

Vendor Nats-Io
Product nats-server
Weakness CWE-290
Published March 25, 2026
Last update March 26, 2026
View on NVD All CVEs

CVSS base score

6.4/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

What the vulnerability does

01Description

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, the NATS message header `Nats-Request-Info:` is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.

Key dates

02Disclosure timeline

March 25, 2026 CVE published
March 26, 2026 Record updated