---
id: CVE-2025-21810
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()

  There are a potential wild pointer dereferences issue regarding APIs
  class_dev_iter_(ini…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()

  There are a potential wild pointer dereferences issue regarding APIs
  class_dev_iter_(ini…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-476
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 6.4, < 6.6.76'
  - 'linux_kernel >= 6.7, < 6.12.13'
  - 'linux_kernel >= 6.13, < 6.13.2'
patched:
  - linux_kernel 6.13.2
published: '2025-02-27'
updated: '2026-07-30'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-21810'
references:
  - url: 'https://git.kernel.org/stable/c/1614e75d1a1b63db6421c7a4bf37004720c7376c'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5c504e9767b947cf7d4e29b811c0c8b3c53242b7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e128f82f7006991c99a58114f70ef61e937b1ac1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f4b9bc823b0cfdebfed479c0e87d6939c7562e87'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00202
epssPercentile: 0.09127
ingestedAt: '2026-07-30T06:53:10.168Z'
---

## Overview

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

driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()

There are a potential wild pointer dereferences issue regarding APIs
class_dev_iter_(init|next|exit)(), as explained by below typical usage:

// All members of @iter are wild pointers.
struct class_dev_iter iter;

// class_dev_iter_init(@iter, @class, ...) checks parameter @class for
// potential class_to_subsys() error, and it returns void type and does
// not initialize its output parameter @iter, so caller can not detect
// the error and continues to invoke class_dev_iter_next(@iter) even if
// @iter still contains wild pointers.
class_dev_iter_init(&iter, ...);

// Dereference these wild pointers in @iter here once suffer the error.
while (dev = class_dev_iter_next(&iter)) { ... };

// Also dereference these wild pointers here.
class_dev_iter_exit(&iter);

Actually, all callers of these APIs have such usage pattern in kernel tree.
Fix by:
- Initialize output parameter @iter by memset() in class_dev_iter_init()
  and give callers prompt by pr_crit() for the error.
- Check if @iter is valid in class_dev_iter_next().

## Affected

- `linux_kernel >= 6.4, < 6.6.76`
- `linux_kernel >= 6.7, < 6.12.13`
- `linux_kernel >= 6.13, < 6.13.2`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.13.2`