SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-6683

Network-delivered update media can make this remote in some pipelines.

MEDIUM 4.6EPSS 0.31%

Does this matter?

Lower severity and a low EPSS score (0.31%). Track it; it rarely justifies an emergency change on its own.

Description

FatFs R0.16 and earlier contains a divide-by-zero in exFAT sync logic bug when crafted metadata causes n_fatent - 2 to be zero during write/sync operations. This maps to CWE-369 (Divide By Zero). 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). Network-delivered update media can make this remote in some pipelines. The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.

CVSS 3.1
4.6 MEDIUMCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.31% probability · 23th percentile
CISA KEV
Not listed
Weakness
CWE-369
Affected
elm-chan/fatfs
Source
44488dab-36db-4358-99f9-bc116477f914

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.