CVE-2026-6684CWE-835

FatFs Infinite Loop in GPT Partition Scan

Medium · published July 1, 2026

CVSS v3.1
4.6
EPSS
0%
Percentile
22.2
In the wild
Unconfirmed
What it is

FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.

The record
Technical detail
CVSS v3.1
4.6 · MEDIUM
Vector
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00306 · 22.2th percentile
Weakness
CWE-835 · Loop with Unreachable Exit Condition ('Infinite Loop')
Published
2026-07-01T13:45Z
EPSS history
Timeline
  • 01 JUL 13:45Z
    FatFs Infinite Loop in GPT Partition Scan
    cvelistv5