New SignDrop Zero-Day Exploit Turns Windows CLFS Security Feature Into SYSTEM Access

Public exploit code has been released targeting a zero-day vulnerability in the Windows Common Log File System (CLFS) driver. Dubbed SignDrop, the exploit abuses path redirection within the driver’s log-authentication feature. Local attackers can leverage companion file creation to escalate privileges and achieve full SYSTEM access. Administrators should monitor for official patches from Microsoft to mitigate this local privilege escalation risk.