---
id: CVE-2025-38692
title: 'exfat: add cluster chain loop check for dir'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  exfat: add cluster chain loop check for dir

  An infinite loop may occur if the following conditions occur due to
  file system corruption.

  (1) Condition for exfat_count_…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    1715f0996f7baf817c73613aeda500c4f73a6bd6
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    868f23286c1a13162330fa6c614fe350f78e3f82
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    aa8fe7b7b73d4c9a41bb96cb3fb3092f794ecb33
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    e2066ca3ef49a30920d8536fa366b2a183a808ee
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    4c3cda20c4cf1871e27868d08fda06b79bc7d568
  - >-
    Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 <
    99f9a97dce39ad413c39b92c90393bbd6778f3fd
  - Linux 5.7
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:07:19.990218Z'
published: '2025-09-04'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:12:53.072Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-38692'
references:
  - url: 'https://git.kernel.org/stable/c/1715f0996f7baf817c73613aeda500c4f73a6bd6'
  - url: 'https://git.kernel.org/stable/c/868f23286c1a13162330fa6c614fe350f78e3f82'
  - url: 'https://git.kernel.org/stable/c/aa8fe7b7b73d4c9a41bb96cb3fb3092f794ecb33'
  - url: 'https://git.kernel.org/stable/c/e2066ca3ef49a30920d8536fa366b2a183a808ee'
  - url: 'https://git.kernel.org/stable/c/4c3cda20c4cf1871e27868d08fda06b79bc7d568'
  - url: 'https://git.kernel.org/stable/c/99f9a97dce39ad413c39b92c90393bbd6778f3fd'
tags:
  - cve.org
epss: 0.00166
epssPercentile: 0.05914
ingestedAt: '2026-11-03T19:53:18.504Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

exfat: add cluster chain loop check for dir

An infinite loop may occur if the following conditions occur due to
file system corruption.

(1) Condition for exfat_count_dir_entries() to loop infinitely.
    - The cluster chain includes a loop.
    - There is no UNUSED entry in the cluster chain.

(2) Condition for exfat_create_upcase_table() to loop infinitely.
    - The cluster chain of the root directory includes a loop.
    - There are no UNUSED entry and up-case table entry in the cluster
      chain of the root directory.

(3) Condition for exfat_load_bitmap() to loop infinitely.
    - The cluster chain of the root directory includes a loop.
    - There are no UNUSED entry and bitmap entry in the cluster chain
      of the root directory.

(4) Condition for exfat_find_dir_entry() to loop infinitely.
    - The cluster chain includes a loop.
    - The unused directory entries were exhausted by some operation.

(5) Condition for exfat_check_dir_empty() to loop infinitely.
    - The cluster chain includes a loop.
    - The unused directory entries were exhausted by some operation.
    - All files and sub-directories under the directory are deleted.

This commit adds checks to break the above infinite loop.

## Affected

- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < 1715f0996f7baf817c73613aeda500c4f73a6bd6`
- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < 868f23286c1a13162330fa6c614fe350f78e3f82`
- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < aa8fe7b7b73d4c9a41bb96cb3fb3092f794ecb33`
- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < e2066ca3ef49a30920d8536fa366b2a183a808ee`
- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < 4c3cda20c4cf1871e27868d08fda06b79bc7d568`
- `Linux >= 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003 < 99f9a97dce39ad413c39b92c90393bbd6778f3fd`
- `Linux 5.7`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.