CVE-2026-32305

{"id": "CVE-2026-32305", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 7.8, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/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": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "HIGH", "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"}}]}, "published": "2026-03-20T11:18:02.360", "references": [{"url": "https://github.com/traefik/traefik/releases/tag/v2.11.41", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/traefik/traefik/releases/tag/v3.6.11", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/traefik/traefik/security/advisories/GHSA-wvvq-wgcr-9q48", "tags": ["Patch", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-287"}, {"lang": "en", "value": "CWE-1188"}]}], "descriptions": [{"lang": "en", "value": "Traefik is an HTTP reverse proxy and load balancer. Versions 2.11.40 and below, 3.0.0-beta1 through 3.6.11, and 3.7.0-ea.1 are vulnerable to mTLS bypass through the TLS SNI pre-sniffing logic related to fragmented ClientHello packets. When a TLS ClientHello is fragmented across multiple records, Traefik's SNI extraction may fail with an EOF and return an empty SNI. The TCP router then falls back to the default TLS configuration, which does not require client certificates by default. This allows an attacker to bypass route-level mTLS enforcement and access services that should require mutual TLS authentication. This issue is patched in versions 2.11.41, 3.6.11 and 3.7.0-ea.2."}, {"lang": "es", "value": "Traefik es un proxy inverso HTTP y balanceador de carga. Las versiones 2.11.40 e inferiores, 3.0.0-beta1 hasta 3.6.11, y 3.7.0-ea.1 son vulnerables a un bypass de mTLS a trav\u00e9s de la l\u00f3gica de pre-sniffing de SNI de TLS relacionada con paquetes ClientHello fragmentados. Cuando un ClientHello de TLS se fragmenta en m\u00faltiples registros, la extracci\u00f3n de SNI de Traefik puede fallar con un EOF y devolver un SNI vac\u00edo. El router TCP entonces recurre a la configuraci\u00f3n TLS predeterminada, que no requiere certificados de cliente por defecto. Esto permite a un atacante saltarse la aplicaci\u00f3n de mTLS a nivel de ruta y acceder a servicios que deber\u00edan requerir autenticaci\u00f3n TLS mutua. Este problema est\u00e1 parcheado en las versiones 2.11.41, 3.6.11 y 3.7.0-ea.2."}], "lastModified": "2026-03-24T15:15:55.563", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "440A1D58-1FFD-408A-A6B0-25E23F5C24AF", "versionEndExcluding": "2.11.41"}, {"criteria": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "90620FAD-4F72-465E-A744-D62559C92F18", "versionEndIncluding": "3.6.11", "versionStartIncluding": "3.0.0"}, {"criteria": "cpe:2.3:a:traefik:traefik:3.7.0:ea1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7881B288-5141-4508-AB71-3F7586168437"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}