vulns-2026-fatfs-chance

ELM FatFs Vulnerability Research Dieses Repository dokumentiert sechs bestätigte Sicherheitslücken in FatFs zusammen mit einer Test-Harness, einem Fuzzer und einem eigenständigen Generator für Exploit-Disk-Images. Der ursprüngliche FatFs-Quellcode befindet sich im Verzeichnis FatFs-R0.16. Dieses...

CVE-2026-6688

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...

CVE-2026-6685

Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority following a notification that the vulnerability determination was made in error. After review, the CNA confirmed the erroneous finding. Thanks to David Brown for reaching out about this issue...

CVE-2026-6683

FatFs R0.16 and earlier contains a divide-by-zero in exFAT sync logic bug when crafted metadata causes nfatent - 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...

CVE-2026-6686

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

CVE-2026-6682

In FatFS R0.16 and earlier contains a FAT32 integer overflow bug in mountvolume where fasize = fs-nfats 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:...

CVE-2026-6687

FatFs R0.16 and earlier contains a stack overflow bug in fgetlabel because exFAT label length XDIRNumLabel is trusted without enforcing spec maximums. This maps to CWE-121 Stack-based Buffer Overflow. 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 estimate...

CVE-2026-6688 FatFs Buffer Overflow via Unbounded LFN Filename Copy

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...

CVE-2026-6688 FatFs Buffer Overflow via Unbounded LFN Filename Copy

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...

CVE-2026-6688

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...

CVE-2026-6688

CVE-2026-6688 affects FatFs R0.16 and earlier . It is a downstream-caller vulnerability in FatFs long filename handling: with LFN enabled, fno.fname can be up to 255 characters , and callers copy it into short fixed buffers without bounds checks, causing a buffer overflow (CWE-120). CVSS v3.1: AV...

CVE-2026-6687

CVE-2026-6687 affects FatFs R0.16 and earlier. Root cause: f_getlabel() trusts exFAT label length (XDIR_NumLabel) beyond the spec maximums, causing a stack-based buffer overflow (CWE-121). Documented impact per CVSS: high for confidentiality, integrity, and availability. Exploitation status is no...

CVE-2026-6687 FatFs Stack Buffer Overflow via Uncapped exFAT Label Length

FatFs R0.16 and earlier contains a stack overflow bug in fgetlabel because exFAT label length XDIRNumLabel is trusted without enforcing spec maximums. This maps to CWE-121 Stack-based Buffer Overflow. 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 estimate...

EUVD-2026-40999

FatFs R0.16 and earlier contains a stack overflow bug in fgetlabel because exFAT label length XDIRNumLabel is trusted without enforcing spec maximums. This maps to CWE-121 Stack-based Buffer Overflow. 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 estimate...

CVE-2026-6687

FatFs R0.16 and earlier contains a stack overflow bug in fgetlabel because exFAT label length XDIRNumLabel is trusted without enforcing spec maximums. This maps to CWE-121 Stack-based Buffer Overflow. 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 estimate...

EUVD-2026-40998

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

CVE-2026-6686 FatFs Use of Uninitialized Clusters After Seek Past EOF

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

CVE-2026-6686

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...

CVE-2026-6686

FatFs CVE-2026-6686 affects FatFs R0.16 and earlier. The issue is an uninitialized cluster exposure when f_lseek() extends a file beyond EOF without zero-filling newly allocated clusters, mapping to CWE-908 (Use of Uninitialized Resource). The root cause is not zero-filling or initializing cluste...

CVE-2026-6686 FatFs Use of Uninitialized Clusters After Seek Past EOF

FatFs R0.16 and earlier contains an uninitialized cluster exposure when flseek extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 Use of Uninitialized Resource. Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N 4.6, Medium. The...