CVE-2025-21915

Published Apr 1, 2025

Last updated 3 months ago

CVSS high 7.0

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: cdx: Fix possible UAF error in driver_override_show() Fixed a possible UAF problem in driver_override_show() in drivers/cdx/cdx.c This function driver_override_show() is part of DEVICE_ATTR_RW, which includes both driver_override_show() and driver_override_store(). These functions can be executed concurrently in sysfs. The driver_override_store() function uses driver_set_override() to update the driver_override value, and driver_set_override() internally locks the device (device_lock(dev)). If driver_override_show() reads cdx_dev->driver_override without locking, it could potentially access a freed pointer if driver_override_store() frees the string concurrently. This could lead to printing a kernel address, which is a security risk since DEVICE_ATTR can be read by all users. Additionally, a similar pattern is used in drivers/amba/bus.c, as well as many other bus drivers, where device_lock() is taken in the show function, and it has been working without issues. This potential bug was detected by our experimental static analysis tool, which analyzes locking APIs and paired functions to identify data races and atomicity violations.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-416
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-416

Social media

Hype score
Not currently trending

  1. CVE-2025-21915 In the Linux kernel, the following vulnerability has been resolved: cdx: Fix possible UAF error in driver_override_show() Fixed a possible UAF problem in driver_ove… https://t.co/iLAOBuiUuu

    @CVEnew

    2 Apr 2025

    175 Impressions

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Configurations

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References

Sources include official advisories and independent security research.