The detection rule titled 'Fax Service DLL Search Order Hijack' targets a vulnerability in the Windows Fax service where the service attempts to load a non-existent DLL, ualapi.dll. This behavior can be exploited by an attacker to load their own malicious DLL, thus compromising the system. The rule focuses on monitoring events where the fax service (fxssvc.exe) tries to load ualapi.dll, particularly if the loading path begins with 'C:\Windows\WinSxS\', which is an indication of a legitimate system component. If the fax service executes an image that ends with the name of the target DLL, and it does not originate from the supposed secure system folder, an alert is triggered. The overall priority of this detection is set to 'high' due to the significant potential impact on system security and integrity. This rule is part of the ATT&CK framework, specifically mapping to techniques for persistence and defense evasion.