The 'Removable Media Detected' rule focuses on identifying threats arising from the use of removable media to introduce malware into systems, particularly in environments that may be air-gapped or otherwise isolated. Adversaries often exploit weaknesses in autorun functions, allowing malicious executables to run automatically upon insertion of the media. This technique can facilitate lateral movement within a network by replacing or modifying legitimate executable files on the removable device to mislead users into executing malware. The detection mechanism relies on monitoring Windows event logs, specifically EventCode 6416, which indicates the presence of removable media. Through the use of extraction (rex) commands and statistical functions within Splunk, this rule aggregates relevant data, including user and process information, timestamps, and device details, to identify potential threats. The rule is associated with various advanced persistent threat (APT) actors and also cites specific software used in such attacks, providing a comprehensive alerting mechanism for system administrators to take timely action against removable media threats.