CVE-2026-73253

{"id": "CVE-2026-73253", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-73253", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-08-20T18:33:38.834878Z"}}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.1, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 9.1, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "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": "cesanta", "product": "mongoose", "versions": [{"status": "affected", "version": "< 7.22"}]}]}], "published": "2026-08-20T18:16:45.940", "references": [{"url": "https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/cesanta/mongoose/pull/3611", "tags": ["Issue Tracking", "Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/cesanta/mongoose/releases/tag/7.22", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-jp6g-796f-39vp", "tags": ["Exploit", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-jp6g-796f-39vp", "tags": ["Exploit", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-295"}]}], "descriptions": [{"lang": "en", "value": "Mongoose is an embedded web server and network library. Prior to version 7.22, an on-path network attacker with a wildcard certificate for a parent domain can impersonate deeper subdomains to a client using the built-in TLS stack. The mg_tls_verify_cert_san() and mg_tls_verify_cert_cn() functions in src/tls_builtin.c call mg_match(), whose wildcard can cross DNS label boundaries, so a pattern such as *.example.com can match foo.bar.example.com. The resulting hostname verification bypass permits interception and modification of TLS traffic. This issue is fixed in version 7.22."}, {"lang": "es", "value": "Mongoose es un servidor web incrustado y una biblioteca de red. Antes de la versi\u00f3n 7.22, un atacante de red en la ruta con un certificado comod\u00edn para un dominio padre puede suplantar subdominios m\u00e1s profundos a un cliente utilizando la pila TLS integrada. Las funciones mg_tls_verify_cert_san() y mg_tls_verify_cert_cn() en src/tls_builtin.c llaman a mg_match(), cuyo comod\u00edn puede cruzar los l\u00edmites de las etiquetas DNS, por lo que un patr\u00f3n como '*.example.com' puede coincidir con 'foo.bar.example.com'. La omisi\u00f3n resultante de la verificaci\u00f3n del nombre de host permite la interceptaci\u00f3n y modificaci\u00f3n del tr\u00e1fico TLS. Este problema est\u00e1 solucionado en la versi\u00f3n 7.22."}], "lastModified": "2026-10-18T20:10:00.110", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "455C6F41-72BB-40DA-BF44-9D7C6B0C2EB5", "versionEndExcluding": "7.22"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}