{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6683","assignerOrgId":"44488dab-36db-4358-99f9-bc116477f914","state":"PUBLISHED","assignerShortName":"runZero","dateReserved":"2026-04-20T15:06:19.048Z","datePublished":"2026-07-01T13:41:11.337Z","dateUpdated":"2026-07-01T15:24:56.449Z"},"containers":{"cna":{"providerMetadata":{"orgId":"44488dab-36db-4358-99f9-bc116477f914","shortName":"runZero","dateUpdated":"2026-07-01T14:11:06.688Z"},"title":"FatFs Divide-by-Zero in exFAT Sync","datePublic":"2026-07-01T13:00:00.000Z","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-369","description":"CWE-369 Divide by zero","type":"CWE"}]}],"affected":[{"vendor":"ChaN","product":"FatFs","versions":[{"status":"affected","version":"0","lessThanOrEqual":"R0.16","versionType":"custom"}],"defaultStatus":"unaffected"}],"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.","supportingMedia":[{"type":"text/html","base64":false,"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."}]}],"references":[{"url":"https://www.runzero.com/blog/fatfs-bugs/","tags":["third-party-advisory"]},{"url":"https://github.com/runZeroInc/vulns-2026-fatfs-chance","tags":["technical-description"]},{"url":"https://elm-chan.org/fsw/ff/","tags":["product"]},{"url":"https://www.runzero.com/advisories/fatfs-exfat-divide-by-zero-cve-2026-6683","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"PHYSICAL","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseSeverity":"MEDIUM","baseScore":4.6,"vectorString":"CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}}],"credits":[{"lang":"en","value":"HD Moore of runZero, Inc.","type":"finder"},{"lang":"en","value":"Tod Beardsley of runZero, Inc.","type":"coordinator"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.2"}},"adp":[{"references":[{"url":"https://github.com/runZeroInc/vulns-2026-fatfs-chance","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-01T15:24:38.147110Z","id":"CVE-2026-6683","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-01T15:24:56.449Z"}}]}}