Microsoft has made an adjustment to Windows Hello Facial Recognition that affects its functionality in dimly lit environments due to a security vulnerability. This change, introduced in the April 2025 Patch Tuesday updates for Windows 11 and Windows 10, requires color cameras to detect a visible face for sign-in. The update addresses a Windows Hello Spoofing vulnerability that was being exploited. Previously, the feature could identify users in low-light conditions using near-infrared imaging technology. Users have reported a workaround by disabling the webcam in Device Manager, allowing IR sensors to authenticate in low light.