The GameDriverX64.sys kernel-mode anti-cheat driver (v7.23.4.7 and earlier) contains an access control vulnerability in one of its IOCTL handlers. A user-mode process can open a handle to the driver device and send specially crafted IOCTL requests. These requests are executed in kernel-mode context without proper authentication or access validation, allowing the attacker to terminate arbitrary processes, including critical system and security services, without requiring administrative privileges.