Techniques
Sample rules
Office Application Drop Executable
- source: splunk
- technicques:
- T1566
- T1566.001
Description
This search is to detect a suspicious MS office application that drops or creates executables or scripts in a Windows Operating System. This behavior is commonly seen in spear phishing office attachment where it drop malicious files or script to compromised the host. It might be some normal macro may drop script or tools as part of automation but still this behavior is reallly suspicious and not commonly seen in normal office application
Detection logic
| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Processes where Processes.process_name IN ("winword.exe","excel.exe","powerpnt.exe","mspub.exe","visio.exe","wordpad.exe","wordview.exe","onenote.exe","onenotem.exe","onenoteviewer.exe","onenoteim.exe","msaccess.exe") by _time span=1h Processes.process_id Processes.process_name Processes.process Processes.dest Processes.process_guid
| `drop_dm_object_name(Processes)`
|join process_guid, _time [
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Filesystem where Filesystem.file_name IN ("*.exe","*.dll","*.pif","*.scr","*.js","*.vbs","*.vbe","*.ps1") by _time span=1h Filesystem.dest Filesystem.file_create_time Filesystem.file_name Filesystem.process_guid Filesystem.file_path
| `drop_dm_object_name(Filesystem)`
| fields _time dest file_create_time file_name file_path process_name process_path process process_guid]
| dedup file_create_time
| table dest, process_name, process, file_create_time, file_name, file_path, process_guid
| `office_application_drop_executable_filter`