Secuno
ENNL
Book demo

CVE-2026-6687

Elm-chan Fatfs buffer overflow

7.6 HIGHPublic exploitEPSS 0.35%
  1. Published1 Jul 2026

Description

FatFs R0.16 and earlier contains a stack overflow bug in f_getlabel() because exFAT label length (XDIR_NumLabel) 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 estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Total.

CVSS 3.1 breakdown

Attack vectorPhysical
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

Elm-chan Fatfs≤ r0.16

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-962668.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…
CVE-2026-962648.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…
CVE-2026-962638.2
IBM Power Systems Firmware FW1120.00 through FW1120.01, FW1110.00 through FW1110.31,…
CVE-2026-962628.2
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability…
CVE-2026-1088939.9
A vulnerability was identified in Linksys E1700 up to 1.0.0.4.003. This issue affects…
CVE-2026-10889210.0
A vulnerability was determined in Linksys E1700 1.0.0.4.003. This vulnerability affects…

Frequently asked

Is CVE-2026-6687 being actively exploited?

CVE-2026-6687 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.35%.

How severe is CVE-2026-6687?

CVE-2026-6687 has a CVSS 3.1 base score of 7.6, rated high. EPSS estimates a 0.35% probability of exploitation.

Which products are affected by CVE-2026-6687?

Affected products include Elm-chan Fatfs.

How do I fix CVE-2026-6687?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-6687 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.