A critical zero-day exploit, dubbed YellowKey, has been identified, allowing attackers with physical access to Windows 11 systems to bypass the default BitLocker encryption protections. Published by a researcher known as Nightmare-Eclipse, this exploit compromises the security intended to protect sensitive data on encrypted drives. BitLocker, which uses a trusted platform module (TPM) to secure decryption keys, is a mandatory protection for many organizations, including government contractors. The exploit utilizes a custom FsTx folder, which is associated with Microsoft’s Transactional NTFS file system, enabling attackers to gain full access to the drive contents without needing the BitLocker recovery key. Confirmed by security researchers like Kevin Beaumont and Will Dormann, the exploit raises significant concerns regarding data security for organizations relying on BitLocker. As the details of the exploit become more widely known, immediate attention is necessary to mitigate risks associated with this vulnerability.