CVE-2026-44041

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "modules": ["winvnc", "vncviewer"], "product": "UltraVNC", "vendor": "uvnc", "versions": [{"lessThanOrEqual": "1.8.2.2", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:*", "matchCriteriaId": "593F7EC1-0922-4652-817A-7D57A0F1210D", "versionEndIncluding": "1.8.2.2", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "UltraVNC through 1.8.2.2 contains an out-of-bounds read in the wide-string to multibyte conversion helper. In rfb/dh.cpp:204, the vncWc2Mb() function passes a caller-supplied WCHAR pointer to wcslen() before any bounds check. If the caller provides a wide-character buffer that is not properly NUL-terminated, wcslen() reads past the end of the buffer until it encounters a NUL wchar, resulting in an out-of-bounds read. Under typical Win32 API usage this requires an abnormal caller contract. Impact is limited to a potential information disclosure from adjacent memory regions or a process crash (denial of service) if the over-read crosses a page boundary."}, {"lang": "es", "value": "UltraVNC hasta la versi\u00f3n 1.8.2.2 contiene una lectura fuera de l\u00edmites en el asistente de conversi\u00f3n de cadena ancha a multibyte. En rfb/dh.cpp:204, la funci\u00f3n vncWc2Mb() pasa un puntero WCHAR proporcionado por el llamador a wcslen() antes de cualquier comprobaci\u00f3n de l\u00edmites. Si el llamador proporciona un b\u00fafer de caracteres anchos que no est\u00e1 correctamente terminado en NUL, wcslen() lee m\u00e1s all\u00e1 del final del b\u00fafer hasta que encuentra un wchar NUL, lo que resulta en una lectura fuera de l\u00edmites. Bajo el uso t\u00edpico de la API de Win32, esto requiere un contrato de llamador anormal. El impacto se limita a una potencial revelaci\u00f3n de informaci\u00f3n de regiones de memoria adyacentes o un fallo del proceso (denegaci\u00f3n de servicio) si la lectura excesiva cruza un l\u00edmite de p\u00e1gina."}], "id": "CVE-2026-44041", "lastModified": "2026-10-25T17:10:00.197", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 2.5, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-44041", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-01T13:10:10.152068Z", "version": "2.0.3"}}]}, "published": "2026-07-01T05:16:21.033", "references": [{"source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "tags": ["Product"], "url": "https://github.com/ultravnc/UltraVNC"}, {"source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "tags": ["Product", "Release Notes"], "url": "https://uvnc.com/"}, {"source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "url": "https://www.securin.io/zero-days/cve-2026-44041-vncwc2mb-wcslen-before-bounds-check-ultravnc"}], "sourceIdentifier": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-125"}], "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "type": "Secondary"}]}

{}

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