GHSA-fcjp-h8cc-6879Published

NATS is vulnerable to MQTT hijacking via Client ID

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cve-program · CVE-2026-33215

Published

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.

Source published: 24 Mar 2026 20:55:53 UTC
Source modified: 25 Mar 2026 13:05:12 UTC
Saved here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

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 · 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L

euvd · EUVD-2026-15017

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 24, 2026, 8:55:53 PM

dateUpdated: Mar 25, 2026, 1:05:12 PM

4 related source bulletins · separate from aliases

RHSA-2026:22347: Red Hat Security Advisory: Multicluster Global Hub 1.4.5 security update

CVE-2026-4427 · CVE-2026-21728 · CVE-2026-25679 · CVE-2026-27137 · CVE-2026-27889 · CVE-2026-29785 · CVE-2026-32280 · CVE-2026-32281 · CVE-2026-32282 · CVE-2026-32283 · CVE-2026-32285 · CVE-2026-32286 · CVE-2026-33186 · CVE-2026-33215 · CVE-2026-33216 · CVE-2026-33217 · CVE-2026-33218 · CVE-2026-33219 · CVE-2026-33247 · CVE-2026-33413 · CVE-2026-33487 · CVE-2026-33810 · CVE-2026-33813 · CVE-2026-33997 · CVE-2026-34040 · CVE-2026-34986 · CVE-2026-40890 · CVE-2026-41602 · CVE-2026-41603 · CVE-2026-41604 · CVE-2026-41605 · CVE-2026-41606 · CVE-2026-41607 · CVE-2026-41636 · CVE-2026-43869

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

RHSA-2026:21769: Red Hat Security Advisory: Multicluster Global Hub 1.5.4 security update

RHSA-2026:23345: Red Hat Security Advisory: Multicluster Global Hub 1.6.2 security update

Source published: Mar 24, 2026, 8:55:53 PM (timezone not stated)
Source modified: Mar 25, 2026, 1:05:12 PM (timezone not stated)
Saved here: 15 Nov 2026 09:38:04 UTC
Source terms: ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

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 · 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L

nvd · CVE-2026-33215

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-287 · CWE-488

Original publisher date fields

published: 2026-03-24T21:16:28.640

lastModified: 2026-06-17T10:37:08.227

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: 24 Mar 2026 21:16:28 UTC
Source modified: 17 Jun 2026 10:37:08 UTC
Saved here: 25 Oct 2026 08:17:18 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 3.1 · [email protected] · Secondary · 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L

CVSS 3.1 · [email protected] · Primary · 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

osv · GHSA-fcjp-h8cc-6879

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 provides an MQTT client interface. ### Problem Description Sessions and Messages can by hijacked via MQTT Client ID malfeasance. ### Affected Versions Any version before v2.12.6 or v2.11.15 ### Workarounds None. ### Resources * This document is canonically: <https://advisories.nats.io/CVE/secnote-2026-06.txt> * GHSA advisory: <https://github.com/nats-io/nats-server/security/advisories/GHSA-fcjp-h8cc-6879> * MITRE CVE entry: <https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33215>

Source published: 24 Mar 2026 21:39:52 UTC
Source modified: 10 Sep 2026 03:51:00 UTC
Saved here: 24 Oct 2026 13:19:41 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

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:H/PR:N/UI:N/S:U/C:H/I:N/A:L

Publisher rating · MODERATE

osv · GO-2026-4833

Published

NATS is vulnerable to MQTT hijacking via Client ID in github.com/nats-io/nats-server

Source published: 26 Mar 2026 20:33:05 UTC
Source modified: 27 Mar 2026 17:29:30 UTC
Saved here: 24 Oct 2026 13:19:41 UTC
Source terms: OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

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.