CVE-2026-33249Incorrect Authorization in Nats-io Nats-server V2

Severity
4.3MEDIUMNVD
EPSS
0.0%
top 92.51%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedMar 25
Latest updateMar 26

Description

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.11.0 and prior to versions 2.11.15 and 2.12.6, a valid client which uses message tracing headers can indicate that the trace messages can be sent to an arbitrary valid subject, including those to which the client does not have publish permission. The payload is a valid trace message and not chosen by the attacker. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds ar

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:NExploitability: 2.8 | Impact: 1.4

Affected Packages5 packages

debiandebian/nats-server< nats-server 2.12.6-1 (forky)
NVDlinuxfoundation/nats-server2.11.02.11.15+1
Gogithub.com/nats-io_nats-server_v22.11.02.11.15+1
Debianlinuxfoundation/nats-server< 2.12.6-1
CVEListV5nats-io/nats-server>= 2.11.0, < 2.11.15, >= 2.12.0-preview.1, < 2.12.6+1

🔴Vulnerability Details

4
OSV
NATS: Message tracing can be redirected to arbitrary subject in github.com/nats-io/nats-server2026-03-26
OSV
CVE-2026-33249: NATS-Server is a High-Performance server for NATS2026-03-25
GHSA
NATS: Message tracing can be redirected to arbitrary subject2026-03-24
OSV
NATS: Message tracing can be redirected to arbitrary subject2026-03-24

📋Vendor Advisories

2
Red Hat
github.com/nats-io/nats-server: NATS-Server: Unauthorized trace message redirection via message tracing headers2026-03-25
Debian
CVE-2026-33249: nats-server - NATS-Server is a High-Performance server for NATS.io, a cloud and edge native me...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-33249 Impact, Exploitability, and Mitigation Steps | Wiz