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OpenAdvisories
Medium · 6.4 CVE-2026-33223 BIT-nats-2026-33223EUVD-2026-15996GHSA-pwx7-fx9r-hr4hGO-2026-4835

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

Published Mar 25, 2026 · Updated Mar 26, 2026 · Assigned by GitHub_M

Description

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.

Affected products

VendorProductAffectedFixed
nats-io nats-server < 2.11.15, >= 2.12.0-RC.1, < 2.12.6 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 nats-server 2.12.6-1 —
Debian 13 nats-server No fix yet —
Debian 12 nats-server No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 nats-server No fix yet —
Ubuntu 25.10 nats-server No fix yet —
Ubuntu 24.04 LTS nats-server No fix yet —
Show 1 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu Pro 26.04 LTS nats-server No fix yet —
ReleasePackageFixed inAdvisory
openSUSE Leap 16.0 govulncheck-vulndb 0.0.20260723T184607-160000.1.1 openSUSE-SU-2026:21483-1
openSUSE Leap 15.6 govulncheck-vulndb 0.0.20260326T203309-150000.1.155.2 SUSE-SU-2026:1135-1
ReleasePackageFixed inAdvisory
Alpine v3.24 nats-server 2.12.6-r0 —
Alpine v3.23 nats-server 2.12.6-r0 —

Wolfi

ReleasePackageFixed inAdvisory
Wolfi rolling k3s +1 1.35.2.1-r4 —
Wolfi rolling k3s-1.32 +1 1.32.13.1-r7 —
Wolfi rolling kine 0.14.15-r1 —
Wolfi rolling nats 0.3.2-r0 —
Wolfi rolling nats-top 0.6.3-r18 —
Wolfi rolling telegraf-1.38 1.38.1-r1 —

Affected packages

EcosystemPackageAffectedFixedRecord
Go github.com/nats-io/nats-server all versions — GHSA-pwx7-fx9r-hr4h
Go github.com/nats-io/nats-server/v2 < 2.11.15 2.11.15 GHSA-pwx7-fx9r-hr4h
Go github.com/nats-io/nats-server/v2 >= 2.12.0-RC.1, < 2.12.6 2.12.6 GHSA-pwx7-fx9r-hr4h
Go github.com/nats-io/nats-server/v2 < 2.11.15 · >= 2.12.0-RC.1, < 2.12.6 2.11.15, 2.12.6 GO-2026-4835

Advisories 3

References