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CVE-2026-6686

FatFs Use of Uninitialized Clusters After Seek Past EOF PUBLISHED

Description (CNA)

FatFs R0.16 and earlier contains an uninitialized cluster exposure when f_lseek() 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 estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.

Affected (CNA)

Vendor / productVersions
ChaN / FatFsaffected 0 through R0.16

CWE

CWE-908

References

ADP enrichment

CISA-ADP

No English description supplied.