VDB-302682 · CVE-2025-21956 · EUVD-2025-9364

Linux Kernel up to 6.1.131/6.6.83/6.12.19/6.13.7 AMD Display normalized_pix_clk privilege escalation

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5.4	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 6.1.131/6.6.83/6.12.19/6.13.7. The affected element is the function normalized_pix_clk of the component AMD Display. The manipulation results in an unknown weakness. This vulnerability is reported as CVE-2025-21956. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 6.1.131/6.6.83/6.12.19/6.13.7. Affected is the function normalized_pix_clk of the component AMD Display. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Assign normalized_pix_clk when color depth = 14 [WHY & HOW] A warning message "WARNING: CPU: 4 PID: 459 at ... /dc_resource.c:3397 calculate_phy_pix_clks+0xef/0x100 [amdgpu]" occurs because the display_color_depth == COLOR_DEPTH_141414 is not handled. This is observed in Radeon RX 6600 XT. It is fixed by assigning pix_clk * (14 * 3) / 24 - same as the rests. Also fixes the indentation in get_norm_pix_clk. (cherry picked from commit 274a87eb389f58eddcbc5659ab0b180b37e92775)

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2025-21956 since 12/29/2024. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 234309 (Debian dsa-5900 : affs-modules-6.1.0-28-4kc-malta-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.132, 6.6.84, 6.12.20 or 6.13.8 eliminates this vulnerability. Applying the patch dc831b38680c47d07e425871a9852109183895cf/a8f77e1658d78e4a8bb227a83bcee67de97f7634/04f90b505ad3a6eed474bbaa03167095fef5203a/27df30106690969f7d63604f0d49ed8e9bffa2cb/79e31396fdd7037c503e6add15af7cb00633ea92 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (234309), EUVD (EUVD-2025-9364) and CERT Bund (WID-SEC-2025-0683). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

Google Container-Optimized OS
Debian Linux
Amazon Linux 2
Red Hat Enterprise Linux
Ubuntu Linux
SUSE Linux
Oracle Linux
RESF Rocky Linux
Dell Avamar
Open Source Linux Kernel
SolarWinds Security Event Manager
Dell NetWorker
Dell Secure Connect Gateway
IBM Security Verify Access

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍