ChaN FatFs up to R0.16 Metadata divide by zero

CVSS Meta Temp Score
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CTI Interest Score
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2.4$0-$5k0.00

Summaryinfo

A vulnerability was found in ChaN FatFs up to R0.16. It has been rated as problematic. The affected element is an unknown function of the component Metadata Handler. The manipulation leads to divide by zero. This vulnerability is uniquely identified as CVE-2026-6683. It is possible to launch the attack on the physical device. No exploit exists.

Detailsinfo

A vulnerability was found in ChaN FatFs up to R0.16 and classified as problematic. This issue affects an unknown function of the component Metadata Handler. The manipulation with an unknown input leads to a divide by zero vulnerability. Using CWE to declare the problem leads to CWE-369. The product divides a value by zero. Impacted is availability. The summary by CVE is:

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.

The weakness was disclosed by Hd Moore. The advisory is shared at runzero.com. The identification of this vulnerability is CVE-2026-6683 since 04/20/2026. The exploitation is known to be easy. An attack has to be approached locally. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.4
VulDB Meta Temp Score: 2.4

VulDB Base Score: 2.4
VulDB Temp Score: 2.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Divide by zero
CWE: CWE-369 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Yes
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/20/2026 CVE reserved
07/01/2026 +72 days Advisory disclosed
07/01/2026 +0 days VulDB entry created
07/01/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: runzero.com
Researcher: Hd Moore
Status: Not defined

CVE: CVE-2026-6683 (🔒)
GCVE (CVE): GCVE-0-2026-6683
GCVE (VulDB): GCVE-100-375557

Entryinfo

Created: 07/01/2026 17:14
Changes: 07/01/2026 17:14 (54)
Complete: 🔍
Cache ID: 216::103

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