BIT-nats-2026-33223Published

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

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cve-program · CVE-2026-33223

Published

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.

Source published: 25 Mar 2026 20:20:00 UTC
Source modified: 26 Mar 2026 17:51:23 UTC
Saved here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

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Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 3.1 · 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

euvd · EUVD-2026-15996

Published

Additional publisher context

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Mar 25, 2026, 8:20:00 PM

dateUpdated: Mar 26, 2026, 5:51:23 PM

1 related source bulletins · separate from aliases

WID-SEC-W-2026-0858: NATS Server: Mehrere Schwachstellen

CVE-2026-33215 · CVE-2026-33216 · CVE-2026-33217 · CVE-2026-33218 · CVE-2026-33219 · CVE-2026-33222 · CVE-2026-33223 · CVE-2026-33246 · CVE-2026-33247 · CVE-2026-33248 · CVE-2026-33249

Source published: Mar 25, 2026, 8:20:00 PM (timezone not stated)
Source modified: Mar 26, 2026, 5:51:23 PM (timezone not stated)
Saved here: 15 Nov 2026 20:52:53 UTC
Source terms: ENISA EUVD · source terms and attribution apply

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Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

EUVD CVSS 3.1 · 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

nvd · CVE-2026-33223

Published

Additional publisher context

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Analyzed

Weakness classifications: CWE-290

Original publisher date fields

published: 2026-03-25T21:16:47.397

lastModified: 2026-06-17T10:37:09.117

1 source CPE criteria · context only

cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 25 Mar 2026 21:16:47 UTC
Source modified: 17 Jun 2026 10:37:09 UTC
Saved here: 25 Oct 2026 08:17:18 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

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CVSS 3.1 · [email protected] · Secondary · 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

CVSS 3.1 · [email protected] · Primary · 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

osv · GHSA-pwx7-fx9r-hr4h

Published

### 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.

Source published: 24 Mar 2026 21:50:05 UTC
Source modified: 10 Sep 2026 03:50:40 UTC
Saved here: 24 Oct 2026 13:19:41 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

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Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Publisher rating · MODERATE

osv · GO-2026-4835

Published

NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing in github.com/nats-io/nats-server

Source published: 26 Mar 2026 20:33:05 UTC
Source modified: 27 Mar 2026 18:26:13 UTC
Saved here: 24 Oct 2026 13:19:41 UTC
Source terms: OSV · upstream source license applies

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Source: osv · OSV · upstream source license applies. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.