CVE-2026-73251

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{"affected": [{"affectedData": [{"product": "mongoose", "vendor": "cesanta", "versions": [{"status": "affected", "version": "< 7.23"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*", "matchCriteriaId": "8E3EDF1E-BF33-4484-B6EF-D6C3374149E7", "versionEndExcluding": "7.23", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Mongoose is an embedded web server and network library. Prior to 7.23, a network attacker can impersonate a TLS server to a Mongoose client configured with a multi-certificate CA bundle. In src/tls_builtin.c, the mg_tls_init() function stores the bundle in tls->ca_bundle_der while tls->ca_der.len remains zero, and mg_tls_recv_cert() uses tls_bundle_find() to accept a Common Name match without calling mg_tls_verify_cert_signature(). A forged self-signed certificate can therefore satisfy hostname and CertificateVerify checks and enable interception, credential disclosure, traffic modification, and malicious responses. This issue is fixed in version 7.23."}, {"lang": "es", "value": "Mongoose es un servidor web incrustado y una biblioteca de red. Antes de la 7.23, un atacante de red puede suplantar un servidor TLS a un cliente Mongoose configurado con un paquete de CA de m\u00faltiples certificados. En src/tls_builtin.c, la funci\u00f3n mg_tls_init() almacena el paquete en tls -> ca_bundle_der mientras que tls -> ca_der.len permanece en cero, y mg_tls_recv_cert() utiliza tls_bundle_find() para aceptar una coincidencia de Nombre Com\u00fan sin llamar a mg_tls_verify_cert_signature(). Un certificado autofirmado falsificado puede, por lo tanto, satisfacer las comprobaciones de nombre de host y CertificateVerify y permitir la interceptaci\u00f3n, la divulgaci\u00f3n de credenciales, la modificaci\u00f3n del tr\u00e1fico y respuestas maliciosas. Este problema est\u00e1 corregido en la versi\u00f3n 7.23."}], "id": "CVE-2026-73251", "lastModified": "2026-10-18T20:10:00.110", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.2, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.3, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-73251", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-08-20T19:50:25.364486Z", "version": "2.0.3"}}]}, "published": "2026-08-20T18:16:45.743", "references": [{"source": "security-advisories@github.com", "tags": ["Patch"], "url": "https://github.com/cesanta/mongoose/commit/2988bc9df3a5efc9539471cb7455975fa25df483"}, {"source": "security-advisories@github.com", "tags": ["Release Notes"], "url": "https://github.com/cesanta/mongoose/releases/tag/7.23"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-qj6j-2692-v2r8"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-295"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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