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.
Metrics
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HWeakness enumeration
Affected software
No affected versions have been published.
Timeline
- Published
- Jul 1, 2026
- Last modified
- Oct 25, 2026
- NVD status
- Analyzed