Found in the wild: 2 Secure Boot exploits. Microsoft is patching only 1 of them.
1 min read
Summary
A monthly security update from Microsoft has patched a Secure Boot bypass vulnerability affecting more than 50 manufacturers of devices.
Secure Boot is designed to prevent access to devices by ensuring that only secure operating system images are loaded during boot up.
However, researchers have discovered two exploits that completely bypass this protection.
One of these exploits can be blocked by Microsoft’s patch, but the other remains viable.
The underlying cause of the vulnerability centres on a critical vulnerability in a tool used to flash firmware images on the motherboards of DT Research devices, and it is authenticated by a certificate signed by Microsoft.
This certificate comes pre-installed on affected machines and its purpose is to authenticate so-called shims for loading Linux.
Microsoft’s patch adds cryptographic hashes for several variants of the DT Research tool to a block list.
