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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-6682 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://elm-chan.org/fsw/ff/ runZero
https://github.com/runZeroInc/vulns-2026-fatfs-chance CISA-ADP, runZero
https://www.runzero.com/advisories/fatfs-fat32-int-of-mnt-cve-2026-6682/ runZero
https://www.runzero.com/blog/fatfs-bugs/ runZero

Weakness Enumeration

CWE-ID CWE Name Source
CWE-190 Integer Overflow or Wraparound runZero  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-6682
NVD Published Date:
07/01/2026
NVD Last Modified:
07/01/2026
Source:
runZero