CVE-2026-6683

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "FatFs", "vendor": "ChaN", "versions": [{"lessThanOrEqual": "R0.16", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "44488dab-36db-4358-99f9-bc116477f914"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:elm-chan:fatfs:*:*:*:*:*:*:*:*", "matchCriteriaId": "B99160BB-C4F5-4DA0-9FC9-0723E0633E00", "versionEndIncluding": "r0.16", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "FatFs R0.16 and earlier contains a divide-by-zero in exFAT sync logic bug when crafted metadata causes n_fatent - 2 to be zero during write/sync operations. This maps to CWE-369 (Divide By Zero). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). Network-delivered update media can make this remote in some pipelines. The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial."}, {"lang": "es", "value": "FatFs R0.16 y anteriores contiene una divisi\u00f3n por cero en un error de la l\u00f3gica de sincronizaci\u00f3n de exFAT cuando metadatos manipulados causan que n_fatent - 2 sea cero durante operaciones de escritura/sincronizaci\u00f3n. Esto se mapea a CWE-369 (Divisi\u00f3n por Cero). Vector CVSS v3.1 estimado: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Media). Medios de actualizaci\u00f3n entregados por red pueden hacer que esto sea remoto en algunas cadenas de suministro. Los vectores SSVC de CISA estimados son Explotaci\u00f3n: PoC, Impacto T\u00e9cnico: Parcial."}], "id": "CVE-2026-6683", "lastModified": "2026-10-25T17:10:00.197", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "PHYSICAL", "availabilityImpact": "HIGH", "baseScore": 4.6, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 0.9, "impactScore": 3.6, "source": "44488dab-36db-4358-99f9-bc116477f914", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-6683", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-01T15:24:38.147110Z", "version": "2.0.3"}}]}, "published": "2026-07-01T15:17:12.443", "references": [{"source": "44488dab-36db-4358-99f9-bc116477f914", "tags": ["Product"], "url": "https://elm-chan.org/fsw/ff/"}, {"source": "44488dab-36db-4358-99f9-bc116477f914", "tags": ["Third Party Advisory", "Exploit"], "url": "https://github.com/runZeroInc/vulns-2026-fatfs-chance"}, {"source": "44488dab-36db-4358-99f9-bc116477f914", "tags": ["Third Party Advisory"], "url": "https://www.runzero.com/advisories/fatfs-exfat-divide-by-zero-cve-2026-6683"}, {"source": "44488dab-36db-4358-99f9-bc116477f914", "tags": ["Third Party Advisory", "Exploit"], "url": "https://www.runzero.com/blog/fatfs-bugs/"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Third Party Advisory", "Exploit"], "url": "https://github.com/runZeroInc/vulns-2026-fatfs-chance"}], "sourceIdentifier": "44488dab-36db-4358-99f9-bc116477f914", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-369"}], "source": "44488dab-36db-4358-99f9-bc116477f914", "type": "Secondary"}]}

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