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Fencer Intel
high 7.8

CVE-2026-91041 json

FileX fault-tolerant log replay writes past the destination sector when mounting a crafted FAT image

published last mo. modified 22d ago also EUVD-2026-104999 , GHSA-c8cj-fj9j-426v

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository eclipse-threadx/filex. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

Mounting an attacker-controlled FAT image with fault tolerance enabled causes an out-of-bounds heap write during log replay. The write is attacker-positioned and attacker-valued, and on a common embedded memory layout it reaches the FX_MEDIA driver callback, giving control of the instruction pointer.

Patch / fix

  • Eclipse Foundation Eclipse ThreadX - FileX 6.5.2.202603

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
22d ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

  • Eclipse Foundation Eclipse ThreadX - FileX

Classification

Weakness
  • CWE-787 Out-of-bounds Write
  • CWE-1284 Improper Validation of Specified Quantity in Input

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of eclipse-threadx/filex published their own advisory on GitHub. Reviewed sources take precedence over it.