CVE-2026-74449
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, the amdgpu display driver has a divide-by-zero vulnerability in calculate_mcache_setting when the viewport has zero area. This causes a kernel panic and potential underflow on num_mcaches. The fix changes the function to return bool and adds guards to reject the mode when values are zero.
Risk Assessment
A local attacker could trigger a kernel panic (DoS) by manipulating the viewport.
Recommendation
Apply the Linux kernel update containing the fix (commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da).
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport If a plane reaches calculate_mcache_setting with a zero-area viewport, calculate_mcache_setting exits early with num_mcaches == 0 and mvmpg_width/height == 0. This will cause a divide-by-zero panic and can also cause an underflow on num_mcaches. Fix this by changing calculate_mcache_setting to bool and adding guards after each calculate_mcache_row_bytes call. If num_mcaches or mvmpg_width/height is zero, return a false. Callers will propagate the failure as a rejected mode, which prevents the panic. (cherry picked from commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da)