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Vulnerability DatabaseCVE-2025-21956

CVE-2025-21956: 
Linux Kernel vulnerability analysis and mitigation

Overview

A vulnerability was discovered in the Linux kernel affecting the AMD display driver (drm/amd/display) component, specifically related to color depth handling. The issue was identified and disclosed on April 1, 2025, and is tracked as CVE-2025-21956. The vulnerability affects systems using AMD Radeon RX 6600 XT graphics cards (NVD).

Technical details

The vulnerability occurs when the display color depth is set to 14 bits (COLORDEPTH141414) in the AMD display driver. This condition triggers a warning message 'WARNING: CPU: 4 PID: 459 at ... /dcresource.c:3397 calculatephypixclks+0xef/0x100 [amdgpu]' due to improper handling of the normalized pixel clock calculations (NVD).

Impact

The impact of this vulnerability appears to be limited to system warnings and potential display issues when using 14-bit color depth on affected AMD graphics hardware (Debian Security).

Mitigation and workarounds

The vulnerability has been fixed in Linux kernel version 6.1.133-1 for Debian bookworm and version 6.12.22-1 for Debian sid. The fix involves properly assigning the normalized pixel clock value using the formula pix_clk (14 3) / 24 when the color depth is set to 14 bits (Debian Security, Debian Advisory).

Additional resources

Source: This report was generated using AI

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