Secure Boot Security Feature Bypass Vulnerability

A security feature bypass vulnerability exists when Windows Secure Boot improperly applies an affected policy. An attacker who successfully exploited this vulnerability could disable code integrity checks, allowing test-signed executables and drivers to be loaded on a target device. In addition, an attacker could bypass the Secure Boot Integrity Validation for BitLocker and the Device Encryption security features.

To exploit the vulnerability, an attacker must either gain administrative privileges or physical access to a target device to install an affected policy.

The security update addresses the vulnerability by blacklisting affected policies.