CVE-2025-21918: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: Fix NULL pointer access Resources should be released only after all threads that utilize them have been destroyed. This commit ensures that resources are not released prematurely by waiting for the associated workqueue to complete before deallocating them.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.16 — 6.1.133
linux	linux_kernel	6.2 — 6.6.83
linux	linux_kernel	6.7 — 6.12.19
linux	linux_kernel	6.13 — 6.13.7
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/079a3e52f3e751bb8f5937195bdf25c5d14fdff0 https://git.kernel.org/stable/c/46fba7be161bb89068958138ea64ec33c0b446d4 https://git.kernel.org/stable/c/592a0327d026a122e97e8e8bb7c60cbbe7697344 https://git.kernel.org/stable/c/7a735a8a46f6ebf898bbefd96659ca5da798bce0 https://git.kernel.org/stable/c/b13abcb7ddd8d38de769486db5bd917537b32ab1

Other References

https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html

Frequently Asked Questions

What is CVE-2025-21918? +

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: Fix NULL pointer access Resources should be released only after all threads that utilize them have been destroyed. This commit ensures that resources are not released prematurely by waiting for the associated workqueue to complete before deallocating them. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21918? +

CVE-2025-21918 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-21918? +

CVE-2025-21918 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21918? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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