CVE-2026-6685

Rejected after erroneous vulnerability determination

Published Jul 1, 2026 · Updated Jul 1, 2026

The CNA rejected the reported dirty-cache flaw in FatFs after confirming that the vulnerability determination was erroneous. The withdrawn report alleged that unsigned subtraction in f_read() and f_write() skipped stale dirty-cache handling during fragmented-file access. The current CVE record removes the affected-version claim, CWE mapping, severity assessment, and proof-of-concept status, so no exploitable condition remains attributed to this identifier.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

The CNA rejected the reported dirty-cache flaw in FatFs after confirming that the vulnerability determination was erroneous. The withdrawn report alleged that unsigned subtraction in f_read() and f_write() skipped stale dirty-cache handling during fragmented-file access. The current CVE record removes the affected-version claim, CWE mapping, severity assessment, and proof-of-concept status, so no exploitable condition remains attributed to this identifier.

The record

CVE
CVE-2026-6685
Published
Jul 1, 2026
Updated
Jul 1, 2026
Vendor
ChaN
Product
FatFs
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Jul 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=R0.16

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

ChaN · FatFsversion=0 <=R0.16

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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