CVE-2025-21810

Published Feb 27, 2025

Last updated a month ago

CVSS high 7.8

Overview

Description
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().
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-476

Social media

Hype score
Not currently trending

  1. 🚨 CVE-2025-21810 ❓ 🏢 Linux - Linux 🏗️ 7b884b7f24b42fa25e92ed724ad82f137610afaf 🔗 https://t.co/XwK2CwMXIs 🔗 https://t.co/9sgJO55PfU 🔗 https://t.co/7pOwLqIYhL 🔗 https://t.co/YrfM3KOOpi #CyberCron #VulnAlert @Linux https://t.co/bSwH8tNtOo

    @cybercronai

    1 Mar 2025

    29 Impressions

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    0 Replies

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Configurations

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References

Sources include official advisories and independent security research.