References to Advisories, Solutions, and Tools

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Change History

https://github.com/runZeroInc/vulns-2026-fatfs-chance

{"timestamp":"2026-07-01T15:24:38.147110Z","id":"CVE-2026-6683","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}

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.

AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CWE-369

https://elm-chan.org/fsw/ff/

https://github.com/runZeroInc/vulns-2026-fatfs-chance

https://www.runzero.com/advisories/fatfs-exfat-divide-by-zero-cve-2026-6683

https://www.runzero.com/blog/fatfs-bugs/

[{"vendor":"ChaN","product":"FatFs","defaultStatus":"unaffected","versions":[{"version":"0","lessThanOrEqual":"R0.16","versionType":"custom","status":"affected"}]}]