Back Doors for Cross-Signed Windows Drivers

Four undocumented registry values vary the default validation of signatures on kernel-mode code such that Windows 10 may allow cross-signed drivers when it is otherwise documented as requiring Microsoft-signed drivers. This may be welcome for running your own drivers on your own computers without having to send them to Microsoft. Or it may be an unwelcome exposure to software that would install drivers by surprise, including to let malware elevate from administrative access to kernel-mode execution. Setting these values requires administrative access. Their action is subject to System Integrity policy, which provides the best defence.[…]

http://www.geoffchappell.com/notes/security/whqlsettings/