CVE-2026-73258

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{"affected": [{"affectedData": [{"product": "mongoose", "vendor": "cesanta", "versions": [{"status": "affected", "version": "< 7.22"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*", "matchCriteriaId": "455C6F41-72BB-40DA-BF44-9D7C6B0C2EB5", "versionEndExcluding": "7.22", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Mongoose is an embedded web server and network library. Prior to 7.22, a remote attacker can place a lone carriage return or line feed in multipart input processed by mg_http_next_multipart() in src/http.c. The loops comparing s[b] and s[b + 1], and s[h2] and s[h2 + 1], use an incorrect AND condition and stop when either character resembles part of a CRLF terminator. This truncates headers, filenames, or boundaries and can cause an application to accept dangerous content after seeing a misleading Content-Type value. 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 remoto puede colocar un retorno de carro o un salto de l\u00ednea solitario en la entrada multipart procesada por mg_http_next_multipart() en src/http.c. Los bucles que comparan s[b] y s[b + 1], y s[h2] y s[h2 + 1], usan una condici\u00f3n AND incorrecta y se detienen cuando cualquiera de los caracteres se asemeja a parte de un terminador CRLF. Esto trunca encabezados, nombres de archivo o l\u00edmites y puede hacer que una aplicaci\u00f3n acepte contenido peligroso despu\u00e9s de ver un valor de Content-Type enga\u00f1oso. Este problema est\u00e1 solucionado en la versi\u00f3n 7.22."}], "id": "CVE-2026-73258", "lastModified": "2026-10-18T20:10:00.110", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 2.5, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-73258", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-08-20T18:32:20.304577Z", "version": "2.0.3"}}]}, "published": "2026-08-20T18:16:47.323", "references": [{"source": "security-advisories@github.com", "tags": ["Patch"], "url": "https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71"}, {"source": "security-advisories@github.com", "tags": ["Issue Tracking", "Patch"], "url": "https://github.com/cesanta/mongoose/pull/3611"}, {"source": "security-advisories@github.com", "tags": ["Release Notes"], "url": "https://github.com/cesanta/mongoose/releases/tag/7.22"}, {"source": "security-advisories@github.com", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-cc55-8v3r-59p8"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/cesanta/mongoose/security/advisories/GHSA-cc55-8v3r-59p8"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-697"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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