This detection rule identifies the initiation of suspicious msiexec processes that are executed with URLs as parameters. The rule is focused on instances where the Windows Installer service (msiexec) is invoked with command line arguments containing a '://', which typically indicates an attempt to perform a web-based installation or download from an external source. Such behavior can signify malicious actions, including the potential delivery of malware or exploitation techniques, as attackers may employ legitimate Windows utilities in unusual ways to bypass security controls. The rule's effectiveness is contingent upon monitoring process creation events in Windows, specifically targeting command line inputs. False positives can arise in environments where administrative scripts and tools frequently utilize msiexec for legitimate purposes. Link to reference: Trend Micro's blog on related attacks.