A security-feature bypass issue exists in the Windows Secure Boot implementation due to errors in accessing debugging functions during the boot process. This flaw allows an attacker to bypass existing security restrictions. Specifically, the issue can be exploited by triggering a boot error to read the BitLocker decryption key from memory, as the bootloader fails to clear it. Furthermore, attackers can downgrade the bootloader to a vulnerable version to exploit this memory reading flaw, even on fully updated Windows 11 systems with Secure Boot enabled. This vulnerability has been linked to the deployment of UEFI bootkits by the FishMonger threat group to ensure persistence and stealth on targeted government systems.