CVE-2026-33217

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, when using ACLs on message subjects, these ACLs were not applied in the `$MQTT.>` namespace, allowing MQTT clients to bypass ACL checks for MQTT subjects. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://advisories.nats.io/CVE/secnote-2026-07.txt	Vendor Advisory
https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:21769
https://access.redhat.com/errata/RHSA-2026:22347
https://access.redhat.com/errata/RHSA-2026:23345
https://access.redhat.com/security/cve/CVE-2026-33217
https://bugzilla.redhat.com/show_bug.cgi?id=2451446
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33217.json

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-03-25 20:16

Updated : 2026-09-09 13:19

NVD link : CVE-2026-33217

Mitre link : CVE-2026-33217

CVE.ORG link : CVE-2026-33217

JSON object : View

Products Affected

linuxfoundation

nats-server

CWE

CWE-863

Incorrect Authorization

CWE-425

Direct Request ('Forced Browsing')

{"id": "CVE-2026-33217", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-33217", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-03-25T20:07:59.832372Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "impactScore": 4.2, "exploitabilityScore": 2.8}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 3.9}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.8}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "nats-io", "product": "nats-server", "versions": [{"status": "affected", "version": "< 2.11.15"}, {"status": "affected", "version": ">= 2.12.0-RC.1, < 2.12.6"}]}]}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "affectedData": [{"cpes": ["cpe:/a:redhat:multicluster_globalhub:1.4::el9"], "vendor": "Red Hat", "product": "Multicluster Global Hub 1.4.5", "versions": [{"status": "unaffected", "version": "1779579439", "lessThan": "*", "versionType": "rpm"}], "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:multicluster_globalhub:1.6::el9"], "vendor": "Red Hat", "product": "Multicluster Global Hub 1.6.5", "versions": [{"status": "unaffected", "version": "1780167118", "lessThan": "*", "versionType": "rpm"}], "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:multicluster_globalhub:1.5::el9"], "vendor": "Red Hat", "product": "Red Hat multicluster global hub 1.5.3", "versions": [{"status": "unaffected", "version": "1778867753", "lessThan": "*", "versionType": "rpm"}], "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9", "collectionURL": "https://catalog.redhat.com/software/containers/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:openshift:4"], "vendor": "Red Hat", "product": "Red Hat OpenShift Container Platform 4", "packageName": "openshift4/oc-mirror-plugin-rhel9", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unaffected"}]}], "published": "2026-03-25T20:16:32.473", "references": [{"url": "https://advisories.nats.io/CVE/secnote-2026-07.txt", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://access.redhat.com/errata/RHSA-2026:21769", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:22347", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:23345", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-33217", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451446", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33217.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-863"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-425"}]}], "descriptions": [{"lang": "en", "value": "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, when using ACLs on message subjects, these ACLs were not applied in the `$MQTT.>` namespace, allowing MQTT clients to bypass ACL checks for MQTT subjects. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available."}, {"lang": "es", "value": "NATS-Server es un servidor de alto rendimiento para NATS.io, un sistema de mensajer\u00eda nativo de la nube y del borde. Antes de las versiones 2.11.15 y 2.12.6, al usar ACLs en los temas de mensajes, estas ACLs no se aplicaban en el espacio de nombres '$MQTT.>', permitiendo a los clientes MQTT eludir las comprobaciones de ACL para los temas MQTT. Las versiones 2.11.15 y 2.12.6 contienen una correcci\u00f3n. No se conocen soluciones alternativas disponibles."}], "lastModified": "2026-09-09T13:19:23.763", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "13EA156E-2759-4586-A22E-CDEAAD4D610C", "versionEndExcluding": "2.11.15"}, {"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4E347CFB-C56D-4FD8-8DD8-3D34C08D7154", "versionEndExcluding": "2.12.6", "versionStartIncluding": "2.12.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}