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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "matchCriteriaId": "13EA156E-2759-4586-A22E-CDEAAD4D610C", "versionEndExcluding": "2.11.15", "vulnerable": true}, {"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "matchCriteriaId": "4E347CFB-C56D-4FD8-8DD8-3D34C08D7154", "versionEndExcluding": "2.12.6", "versionStartIncluding": "2.12.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "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."}], "id": "CVE-2026-33217", "lastModified": "2026-03-26T17:14:48.727", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "LOW", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 4.2, "source": "security-advisories@github.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 2.5, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-03-25T20:16:32.473", "references": [{"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://advisories.nats.io/CVE/secnote-2026-07.txt"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-863"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{"bugzilla": {"description": "nats-server: github.com/nats-io/nats-server: NATS-Server: Access control bypass via unapplied ACLs in MQTT namespace", "id": "2451446", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451446"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "status": "draft"}, "cwe": "CWE-425", "details": ["A flaw was found in NATS-Server. 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."], "mitigation": {"lang": "en:us", "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."}, "name": "CVE-2026-33217", "package_state": [{"cpe": "cpe:/a:redhat:multicluster_globalhub", "fix_state": "Affected", "package_name": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9", "product_name": "Multicluster Global Hub"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift4/oc-mirror-plugin-rhel9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-03-25T19:43:40Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-33217\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-33217\nhttps://advisories.nats.io/CVE/secnote-2026-07.txt\nhttps://github.com/nats-io/nats-server/security/advisories/GHSA-jxxm-27vp-c3m5"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2.11.15)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2.12.0-RC.1,2.12.6)"}}], "enrichment": {"confidence": 91.0, "confidence_source": "matching", "scores": [{"score": 91.0, "source": "matching"}]}, "original": {"product": "nats-server", "source": "cna", "vendor": "nats-io"}, "product": "nats_server", "vendor": "nats"}], "analysis": {"en": {"generated_at": "2026-03-26T18:55:27.317557+00:00", "value": {"mitigation_remediation": ["Upgrade NATS\u2011Server to version 2.11.15 or 2.12.6 or later."], "summary": {"action": "Immediate Patch", "impact": "ACL bypass permits unauthorized MQTT topic access"}, "threat_synthesis": {"affected_systems": "The vulnerability affects the NATS\u2011io NATS\u2011Server product. Any installation running a version older than 2.11.15 or 2.12.6 is exposed; the CPE string indicates the Linux Foundation\u2019s NATS\u2011Server.", "description_and_impact": "Prior to NATS\u2011Server versions 2.11.15 and 2.12.6, message subject ACLs were not enforced for the $MQTT.> namespace. An MQTT client can therefore publish or subscribe to subjects that should be restricted, revealing sensitive information or allowing tampering with traffic. The weakness arises from improper ACL enforcement and is classified as CWE\u2011425 and CWE\u2011863.", "risk_and_exploitability": "The CVSS score of 7.1 denotes high severity, while the EPSS score of less than 1 percent indicates a relatively low likelihood of exploitation in the wild. The issue is not currently listed in the CISA KEV catalog. Based on the description, the attack vector is likely a legitimate MQTT client that connects to the server; no special authentication bypass is required. Exploitation would allow an attacker to read or publish to prohibited subjects, compromising confidentiality and integrity of messaging."}}}}, "created": "2026-03-25T21:46:22.168814+00:00", "updated": "2026-03-27T09:30:13.757077+00:00", "vendors": ["nats", "nats$PRODUCT$nats_server"]}