CVE-2026-6688EPSS p35.7%
CVE-2026-6688CVE-2026-6688
elm-chan / fatfs
Description
FatFs R0.16 and earlier contains a downstream-caller vulnerability pattern associated with FatFs long filename handling. With LFN enabled, fno.fname can be up to 255 characters; many callers copy it into short fixed buffers without bounds checks, causing overflow. This maps to CWE-120 (Buffer Copy without Checking Size of Input). 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). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.
Scoring
| CVSS | 7.6 () |
| Vector | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| EPSS | 0.43% probability of exploitation · percentile 35.7% · 2026-08-15T12:02:44Z |
| Last modified | 2026-07-02 |