{"id":"CVE-2026-33217","state":"PUBLISHED","title":"NATS allows MQTT clients to bypass ACL checks","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, when using ACLs on message subjects, these ACLs were not applied in the `$MQTT.>` namespace, allowing MQTT clients to bypass ACL checks for MQTT subjects. Versions 2.11.15 and 2.12.6 contain a fix. 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Prior to versions 2.11.15 and 2.12.6, when using ACLs on message subjects, these ACLs were not applied in the `$MQTT.>` namespace, allowing MQTT clients to bypass ACL checks for MQTT subjects. Versions 2.11.15 and 2.12.6 contain a fix. 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When Access Control Lists (ACLs) were configured for message subjects, these controls were not correctly applied within the `$MQTT.>` namespace. This oversight allows MQTT clients to bypass the intended ACL checks, potentially granting unauthorized access to sensitive message subjects. This vulnerability could lead to information disclosure or unauthorized message manipulation."}],"affected":[{"vendor":"Red Hat","product":"Multicluster Global Hub 1.4.5","packageName":"multicluster-globalhub/multicluster-globalhub-grafana-rhel9","defaultStatus":"affected","versions":[{"version":"1779579439","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://catalog.redhat.com/software/containers/","cpes":["cpe:/a:redhat:multicluster_globalhub:1.4::el9"]},{"vendor":"Red Hat","product":"Multicluster Global Hub 1.6.5","packageName":"multicluster-globalhub/multicluster-globalhub-grafana-rhel9","defaultStatus":"affected","versions":[{"version":"1780167118","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://catalog.redhat.com/software/containers/","cpes":["cpe:/a:redhat:multicluster_globalhub:1.6::el9"]},{"vendor":"Red Hat","product":"Red Hat multicluster global hub 1.5.3","packageName":"multicluster-globalhub/multicluster-globalhub-grafana-rhel9","defaultStatus":"affected","versions":[{"version":"1778867753","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://catalog.redhat.com/software/containers/","cpes":["cpe:/a:redhat:multicluster_globalhub:1.5::el9"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","packageName":"openshift4/oc-mirror-plugin-rhel9","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:openshift:4"]}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-33217","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2451446","name":"RHBZ#2451446","tags":["issue-tracking","x_refsource_REDHAT"]},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33217.json","tags":["x_sadp-csaf-vex"]},{"url":"https://access.redhat.com/errata/RHSA-2026:22347","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:23345","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/errata/RHSA-2026:21769","tags":["vendor-advisory","x_refsource_REDHAT"]}],"metrics":[{"other":{"content":{"namespace":"https://access.redhat.com/security/updates/classification/","value":"Important"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":8.1,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"format":"CVSS"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-425","description":"Direct Request ('Forced Browsing')","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"redhat-SADP","orgId":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c","dateUpdated":"2026-09-09T12:04:54.322Z"},"datePublic":"2026-03-25T19:43:40.969Z","solutions":[{"lang":"en","value":"RHSA-2026:22347: Multicluster Global Hub 1.4.5"},{"lang":"en","value":"RHSA-2026:23345: Multicluster Global Hub 1.6.5"},{"lang":"en","value":"RHSA-2026:21769: Red Hat multicluster global hub 1.5.3"}],"timeline":[{"lang":"en","time":"2026-03-25T20:01:47.815Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-03-25T19:43:40.969Z","value":"Made public."}],"workarounds":[{"lang":"en","value":"Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability."}],"x_adpType":"supplier","x_generator":{"engine":"sadp-cli 1.0.0"}}]}}}