CVE-2026-6686

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

EUVD-2026-40998

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

CVE-2026-6686

FatFs CVE-2026-6686 affects FatFs R0.16 and earlier. The issue is an uninitialized cluster exposure when f_lseek() extends a file beyond EOF without zero-filling newly allocated clusters, mapping to CWE-908 (Use of Uninitialized Resource). The root cause is not zero-filling or initializing cluste...