The 'Hacktool Ruler' detection rule is designed to identify events generated when the Ruler hacktool, created by Sensepost, is utilized. This tool is often associated with various attack techniques such as credential harvesting and NTLM relay attacks. The rule employs specific Event IDs that correspond to security events in Windows systems, particularly focusing on `Event ID 4776` (which indicates NTLM authentication failures) when the workstation is named 'RULER.' It also checks for `Event ID 4624` (successful logon) and `Event ID 4625` (failed logon) that occur against the same workstation. The detection condition is met if any of these events are triggered. This rule helps in monitoring suspicious activities tied to the Ruler tool, which attackers might exploit. It is vital for organizations to remain vigilant against such techniques that can lead to unauthorized access and potential data breaches, as indicated in the various references provided.