CVE-2025-21989: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix missing .is_two_pixels_per_container Starting from 6.11, AMDGPU driver, while being loaded with amdgpu.dc=1, due to lack of .is_two_pixels_per_container function in dce60_tg_funcs, causes a NULL pointer dereference on PCs with old GPUs, such as R9 280X. So this fix adds missing .is_two_pixels_per_container to dce60_tg_funcs. (cherry picked from commit bd4b125eb949785c6f8a53b0494e32795421209d)

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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	6.11 — 6.12.20
linux	linux_kernel	6.13 — 6.13.8
linux	linux_kernel	All
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/36d04c9313d8d83ead92242f037099ac73e02120 https://git.kernel.org/stable/c/e204aab79e01bc8ff750645666993ed8b719de57 https://git.kernel.org/stable/c/fefa811e616b5d0b555ed65743e528a0a8a0b377

Frequently Asked Questions

What is CVE-2025-21989? +

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix missing .is_two_pixels_per_container Starting from 6.11, AMDGPU driver, while being loaded with amdgpu.dc=1, due to lack of .is_two_pixels_per_container function in dce60_tg_funcs, causes a NULL pointer dereference on PCs with old GPUs, such as R9 280X. So this fix adds missing .is_two_pixels_per_container to dce60_tg_funcs. (cherry picked from commit bd4b125eb949785c6f8a53b0494e32795421209d) It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-21989? +

CVE-2025-21989 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-2025-21989? +

CVE-2025-21989 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-2025-21989? +

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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