It's not entirely clear how the exploit works. Microsoft says it's investigating.

A cybersecurity researcher has published proof-of-concept (PoC) exploits for two unpatched Microsoft Windows vulnerabilities named YellowKey and GreenPlasma, which are a BitLocker…

YellowKey bypasses BitLocker via WinRE USB FsTx files, exposing Windows 11 and Server 2022/2025 systems.

It's not entirely clear how the exploit works. Microsoft says it's investigating.