Now why would I say this is a backdoor ? The component that is responsible for this bug is not present anywhere (even in the internet) except inside WinRE image and what makes it raise suspicions is the fact that the exact same component is also present with the exact same name in a normal windows installation but without the functionalities that trigger the bitlocker bypass issue. Why ? I just can’t come up with an explanation beside the fact that this was intentional.
https://github.com/Nightmare-Eclipse/YellowKey
This was part of a set of 4 exploits and yellowkey and greenplasma remain unpatched