CVE-2026-47778

{"id": "CVE-2026-47778", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-47778", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-27T02:52:00.418621Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "HIGH", "confidentialityImpact": "HIGH"}, "impactScore": 3.6, "exploitabilityScore": 0.7}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "envoyproxy", "product": "envoy", "versions": [{"status": "affected", "version": ">= 1.38.0, < 1.38.1"}, {"status": "affected", "version": ">= 1.37.0, < 1.37.3"}, {"status": "affected", "version": ">= 1.36.0, < 1.36.7"}, {"status": "affected", "version": "< 1.35.11"}]}]}], "published": "2026-06-26T18:16:59.480", "references": [{"url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7", "tags": ["Exploit", "Vendor Advisory", "Mitigation"], "source": "security-advisories@github.com"}, {"url": "https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7", "tags": ["Exploit", "Vendor Advisory", "Mitigation"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-158"}]}], "descriptions": [{"lang": "en", "value": "Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a structural flaw was identified in DefaultCertValidator::verifySubjectAltName where the extracted DNS SAN string is cast to a C-style string using .c_str() before being passed to the Utility::dnsNameMatch() algorithm. If the attacker serves a certificate with a dNSName SAN containing an embedded NUL byte, the helper Utility::generalNameAsString captures the complete string including the NUL. However, when .c_str() evaluates it, implicit conversion to absl::string_view inside dnsNameMatch relies on strlen(), prematurely truncating the evaluation context. Envoy evaluates trucated string against the exact required config_san match and returns true, thereby successfully validating the string with the Nul byte for an upstream routing. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1."}, {"lang": "es", "value": "Envoy es un proxy de borde y de servicio de c\u00f3digo abierto dise\u00f1ado para aplicaciones nativas de la nube. Antes de 1.35.11, 1.36.7, 1.37.3 y 1.38.1, se identific\u00f3 una falla estructural en DefaultCertValidator::verifySubjectAltName donde la cadena DNS SAN extra\u00edda se convierte a una cadena de estilo C usando .c_str() antes de ser pasada al algoritmo Utility::dnsNameMatch(). Si el atacante sirve un certificado con un dNSName SAN que contiene un byte NUL incrustado, la funci\u00f3n auxiliar Utility::generalNameAsString captura la cadena completa incluyendo el NUL. Sin embargo, cuando .c_str() lo eval\u00faa, la conversi\u00f3n impl\u00edcita a absl::string_view dentro de dnsNameMatch se basa en strlen(), truncando prematuramente el contexto de evaluaci\u00f3n. Envoy eval\u00faa la cadena truncada contra la coincidencia exacta requerida de config_san y devuelve true, validando as\u00ed exitosamente la cadena con el byte NUL para un enrutamiento ascendente. Esta vulnerabilidad se corrige en 1.35.11, 1.36.7, 1.37.3 y 1.38.1."}], "lastModified": "2026-10-25T17:10:00.197", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3327F1D2-8A35-41E5-B720-06528D0856C0", "versionEndExcluding": "1.35.13"}, {"criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B1146A14-3C49-48C3-BC2A-1BBB202EBD84", "versionEndExcluding": "1.36.9", "versionStartIncluding": "1.36.0"}, {"criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2057BF79-00D1-4154-9DC0-3F278C72F4E1", "versionEndExcluding": "1.37.5", "versionStartIncluding": "1.37.0"}, {"criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2A218AD4-BF4B-46EA-96D7-3B25B7E71AC8", "versionEndExcluding": "1.38.3", "versionStartIncluding": "1.38.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}