CVE-2026-66071

{"id": "CVE-2026-66071", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-66071", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-25T17:53:05.694643Z"}}], "cvssMetricV31": [{"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:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.0, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "rabbitmq", "product": "rabbitmq-server", "versions": [{"status": "affected", "version": ">= 3.13.0, < 3.13.15"}, {"status": "affected", "version": ">= 4.0.0, < 4.0.22"}, {"status": "affected", "version": ">= 4.1.0, < 4.1.11"}, {"status": "affected", "version": ">= 4.2.0, < 4.2.6"}, {"status": "affected", "version": ">= 4.3.0, < 4.3.1"}]}]}], "published": "2026-09-25T17:17:09.987", "references": [{"url": "https://github.com/rabbitmq/rabbitmq-server/commit/9a44124d9c932d6fc7d2a3b945e5a143e547bcb6", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/rabbitmq/rabbitmq-server/commit/c5690583a53789a3bf00cca508b43e8246db0d11", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-89p2-f5cv-x5cg", "tags": ["Exploit", "Third Party Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-400"}]}], "descriptions": [{"lang": "en", "value": "RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15 and 4.0.22 and 4.1.11 and 4.2.6 and 4.3.1, Atom exhaustion: OAuth2 JWT tag: scope values. extractscopes/1 parses scopes of the form .tag: and calls rabbitdatacoercion:toatom() to convert to a tag atom. The token signature is verified first, so the attacker cannot forge scopes , but in IdP configurations where scope content is user-influenced, each login with a novel tag value leaks one In deployments where users can influence the scopes included in their IdP-issued JWT rabbitmqauthbackendoauth2 enabled IdP permits attacker-influenced scope values in signed tokens. This issue is fixed in versions 3.13.15 and 4.0.22 and 4.1.11 and 4.2.6 and 4.3.1."}], "lastModified": "2026-10-15T20:14:57.567", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "603E40A7-6B53-47D4-A522-17B013CE7607", "versionEndExcluding": "3.13.15", "versionStartIncluding": "3.13.0"}, {"criteria": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F9CF5E9C-1315-47E2-B3FB-27A066E256F6", "versionEndExcluding": "4.0.22", "versionStartIncluding": "4.0.0"}, {"criteria": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "01F24286-9982-4592-A370-70E55D6572D5", "versionEndExcluding": "4.1.11", "versionStartIncluding": "4.1.0"}, {"criteria": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7179C053-B8C1-4B72-83EB-456125ED1AAF", "versionEndExcluding": "4.2.6", "versionStartIncluding": "4.2.0"}, {"criteria": "cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "41410FDE-4B5E-4466-B7C4-A62FEBFA0C80", "versionEndExcluding": "4.3.1", "versionStartIncluding": "4.3.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}