This detection rule identifies modifications to the Windows registry that could indicate an attempt to achieve persistence through LSA (Local Security Authority) extensions. Specifically, it monitors changes to the "Extensions" registry value located at \SYSTEM\CurrentControlSet\Control\LsaExtensionConfig\LsaSrv, focusing on the addition of suspicious DLL files. Attackers may append their custom DLLs to this list, which leads to their code being executed during the initialization of LSA services. By analyzing such registry changes, the rule effectively traces the insertion of potentially malicious DLLs, providing a proactive measure against persistence mechanisms that utilize the Local Security Authority subsystem.