CVE-2026-33223

mediumpriority · track · 22EPSS 0.002 · 12 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.21% (12th) EPSS

CVSS 5.4 · medium

Is it mine?

14 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.4

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.5

v3.16.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:Nsecondary · ENISA EU

v3.16.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:Nsecondary · security-advisories@github.comexploitability 3.1 · impact 2.7

v3.16.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:Nsecondary · OSV

v3.15mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-290USCWE-290US

affected products (14)

Products and version ranges known to be affected.

Open Source NATS Server <2.11.15all versionscert_bundDE
Open Source NATS Server <2.12.6all versionscert_bundDE
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Open Source NATS Server< 2.11.15cert_bundDE
Open Source NATS Server< 2.12.6cert_bundDE
nats-io nats-server≤ < 2.11.15enisa_euvdEU
nats-io nats-server2.12.0-RC.1, → 2.12.6enisa_euvdEU
linuxfoundation nats-server< 2.11.15nvdUScpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*
linuxfoundation nats-server2.12.0 → 2.12.6nvdUScpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*
Bitnami nats< 2.11.15osvUSpkg:bitnami/nats
Bitnami nats2.12.0 → 2.12.6osvUSpkg:bitnami/nats
Go github.com/nats-io/nats-serverall versionsosvUSpkg:golang/github.com/nats-io/nats-server
Go github.com/nats-io/nats-server/v2< 2.11.15osvUSpkg:golang/github.com/nats-io/nats-server/v2
Go github.com/nats-io/nats-server/v22.12.0-RC.1 → 2.12.6osvUSpkg:golang/github.com/nats-io/nats-server/v2

advisories (4)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-0858NATS Server: Mehrere SchwachstellenDeutsch2026-03-24csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in NATS Server ausnutzen, um Informationen offenzulegen oder zu manipulieren, einen Denial-of-Service zu verursachen und Sicherheitsmechanismen zu umgehen.
GHSA-pwx7-fx9r-hr4hNATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing2026-03-24ghsa · osvUS
### Background NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing. The nats-server offers a `Nats-Request-Info:` message header, providing information about a request. ### Problem Description 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. ### Affected Versions Any version before v2.12.6 or v2.11.15 ### Workarounds None.
BIT-nats-2026-33223NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing2026-03-27vendor · osvUS
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.
GO-2026-4835NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing in github.com/nats-io/nats-server2026-03-26vendor · osvUS
NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing in github.com/nats-io/nats-server

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv cert_bund nvd NVD CVE.org MITRE

published 2026-03-25modified 2026-06-17

references (8)

External citations — patches, advisories, analysis.

scry

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