CVE-2026-6682
FatFs Integer Overflow in FAT32 Volume Mount
- Published
- Jul 1, 2026
- Updated
- Jul 1, 2026
- Assigning CNA
- runZero
- Evidence observed
- Aug 16, 2026
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HLow · next 30 days
- Percentile
- 25.4%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
Summary
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 (Integer Overflow or Wraparound). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (7.6, High). Remote delivery is also possible in OTA/update pipelines. The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.
Sources
1- vulns-2026-fatfs-chanceResearch
Documented security vulnerabilities in the FatFs embedded filesystem library with CVE details, fuzzing harness, exploit disk-image generator, and supply-chain impact analysis across dozens of downstream firmware projects.
Responsible use
Use vulnerability information only on systems you own or are authorized to test. Kitploit links to public research metadata and does not store exploit code or malicious payloads.