CVE-2026-19874

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{"affected": [{"affectedData": [{"product": "Metal Gear Online 3", "vendor": "Konami", "versions": [{"status": "affected", "version": "1.1.2.8"}]}], "source": "cret@cert.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A heap-based buffer overflow vulnerability exists in Konami's Metal Gear Online 3, originating from improper validation of lobby data fields related to kicked players. The affected function processes a list of kicked player identifiers using the lobby data key \"kick_num\" to determine the number of entries, and individual kicked player IDs supplied via keys in the format \"kicked_id_%i\". The function does not validate that \"kick_num\" falls within the expected bounds. The game design limits matches to a maximum of 16 players, and the corresponding buffer for storing kicked player IDs is sized accordingly. If \"kick_num\" exceeds this limit, the function continues writing the provided player IDs past the end of the intended buffer and into adjacent memory regions. These adjacent regions contain Steam callback handler structures responsible for processing lobby data updates, lobby messages, and other related events. By supplying an oversized \"kick_num\" value and appropriate \"kicked_id_%i\" fields, an attacker can overwrite fields within the callback handler structures, including function pointers and callback argument values. Successful exploitation may enable control-flow hijacking, potentially allowing arbitrary code execution within the game process."}, {"lang": "es", "value": "Una vulnerabilidad de desbordamiento de b\u00fafer basado en mont\u00edculo existe en Metal Gear Online 3 de Konami, originada por una validaci\u00f3n incorrecta de los campos de datos del lobby relacionados con los jugadores expulsados. La funci\u00f3n afectada procesa una lista de identificadores de jugadores expulsados utilizando la clave de datos del lobby 'kick_num' para determinar el n\u00famero de entradas, y los ID de jugadores expulsados individuales proporcionados a trav\u00e9s de claves en el formato 'kicked_id_%i'. La funci\u00f3n no valida que 'kick_num' se encuentre dentro de los l\u00edmites esperados. El dise\u00f1o del juego limita las partidas a un m\u00e1ximo de 16 jugadores, y el b\u00fafer correspondiente para almacenar los ID de los jugadores expulsados tiene un tama\u00f1o acorde. Si 'kick_num' excede este l\u00edmite, la funci\u00f3n contin\u00faa escribiendo los ID de jugadores proporcionados m\u00e1s all\u00e1 del final del b\u00fafer previsto y en regiones de memoria adyacentes. Estas regiones adyacentes contienen estructuras de gestor de retrollamada de Steam responsables de procesar las actualizaciones de datos del lobby, los mensajes del lobby y otros eventos relacionados. Al proporcionar un valor de 'kick_num' sobredimensionado y campos 'kicked_id_%i' apropiados, un atacante puede sobrescribir campos dentro de las estructuras del gestor de retrollamada, incluyendo punteros de funci\u00f3n y valores de argumentos de retrollamada. La explotaci\u00f3n exitosa puede permitir el secuestro del flujo de control, permitiendo potencialmente la ejecuci\u00f3n de c\u00f3digo arbitrario dentro del proceso del juego."}], "id": "CVE-2026-19874", "lastModified": "2026-10-12T15:10:00.207", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.2, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-19874", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-08-24T20:03:35.495374Z", "version": "2.0.3"}}]}, "published": "2026-08-24T15:16:37.577", "references": [{"source": "cret@cert.org", "url": "https://cwe.mitre.org/data/definitions/122.html"}, {"source": "cret@cert.org", "url": "https://kb.cert.org/vuls/id/728712"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://www.kb.cert.org/vuls/id/728712"}], "sourceIdentifier": "cret@cert.org", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-122"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "1.1.2.8"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "Metal Gear Online 3", "source": "cna", "vendor": "Konami"}, "product": "metal_gear_online_3", "vendor": "konami"}], "created": "2026-08-24T18:30:05.886846+00:00", "updated": "2026-08-24T21:30:16.836940+00:00", "vendors": ["konami", "konami$PRODUCT$metal_gear_online_3"]}