What is CVE-2026-6682?

CVE-2026-6682 is a high-severity vulnerability in Chan Fatfs, classified under Integer Overflow or Wraparound. CVSS score: 7.6/10. Published 2026-07-01.

How severe is CVE-2026-6682?

High severity. CVSS v3 base score is 7.6 out of 10.

Integer overflow in Chan Fatfs

CVE-2026-6682

In FatFS R0.16 and earlier contains a FAT32 integer overflow bug in mount_volume() where fasize *= fs->n_fats can wrap, leading to attacker-controlled file-size metadata and unsafe read lengths in downstream callers. This maps to CWE-190 (…

Vulnerability class: Integer Overflow

CVSS v3 metric

CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

Affected products

Chan Fatfs — versions 0

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

44488dab-36db-4358-99f9-bc116477f914 (third-party-advisory)
44488dab-36db-4358-99f9-bc116477f914 (technical-description)
44488dab-36db-4358-99f9-bc116477f914 (product)
44488dab-36db-4358-99f9-bc116477f914 (third-party-advisory)

Frequently asked questions

What is CVE-2026-6682?: CVE-2026-6682 is a high-severity vulnerability in Chan Fatfs, classified under Integer Overflow or Wraparound. CVSS score: 7.6/10. Published 2026-07-01.
How severe is CVE-2026-6682?: High severity. CVSS v3 base score is 7.6 out of 10.