Techniques
Sample rules
Winword Spawning Cmd
- source: splunk
- technicques:
- T1566
- T1566.001
Description
The following analytic identifies instances where Microsoft Word (winword.exe) spawns the command prompt (cmd.exe). This behavior is detected using Endpoint Detection and Response (EDR) telemetry, focusing on process creation events where the parent process is winword.exe. This activity is significant because it is uncommon and often associated with spearphishing attacks, where malicious attachments execute commands via cmd.exe. If confirmed malicious, this could allow an attacker to execute arbitrary commands, potentially leading to further system compromise, data exfiltration, or lateral movement within the network.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name=winword.exe `process_cmd` by Processes.dest Processes.user Processes.parent_process_name Processes.parent_process Processes.original_file_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `winword_spawning_cmd_filter`
Winword Spawning PowerShell
- source: splunk
- technicques:
- T1566
- T1566.001
Description
The following analytic identifies instances where Microsoft Word (winword.exe) spawns a PowerShell process. This behavior is detected using Endpoint Detection and Response (EDR) telemetry, focusing on process creation events where the parent process is winword.exe. This activity is significant because it is uncommon and often associated with spearphishing attacks, where malicious documents execute encoded PowerShell commands. If confirmed malicious, this could allow an attacker to execute arbitrary code, potentially leading to data exfiltration, system compromise, or further lateral movement within the network.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name="winword.exe" `process_powershell` by Processes.dest Processes.user Processes.parent_process_name Processes.parent_process Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `winword_spawning_powershell_filter`
Office Product Spawning Rundll32 with no DLL
- source: splunk
- technicques:
- T1566
- T1566.001
Description
The following analytic detects any Windows Office Product spawning rundll32.exe without a .dll file extension. This behavior is identified using Endpoint Detection and Response (EDR) telemetry, focusing on process and parent process relationships. This activity is significant as it is a known tactic of the IcedID malware family, which can lead to unauthorized code execution. If confirmed malicious, this could allow attackers to execute arbitrary code, potentially leading to data exfiltration, system compromise, or further malware deployment. Immediate investigation and containment are recommended.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name IN ("winword.exe","excel.exe","powerpnt.exe","mspub.exe","visio.exe","onenote.exe","onenotem.exe","onenoteviewer.exe","onenoteim.exe", "msaccess.exe", "Graph.exe","winproj.exe") `process_rundll32` (Processes.process!=*.dll*) by Processes.dest Processes.user Processes.parent_process_name Processes.parent_process Processes.process_name Processes.process Processes.process_id Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `office_product_spawning_rundll32_with_no_dll_filter`
Excel Spawning PowerShell
- source: splunk
- technicques:
- T1003.002
- T1003
Description
The following analytic detects Microsoft Excel spawning PowerShell, an uncommon and suspicious behavior. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where the parent process is “excel.exe” and the child process is PowerShell. This activity is significant because it is often associated with spearphishing attacks, where malicious attachments execute encoded PowerShell commands. If confirmed malicious, this behavior could allow an attacker to execute arbitrary code, potentially leading to data exfiltration, privilege escalation, or persistent access within the environment.
Detection logic
| tstats `security_content_summariesonly` count values(Processes.process) min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name="excel.exe" `process_powershell` by Processes.parent_process Processes.parent_process_name Processes.process_name Processes.user Processes.dest Processes.original_file_name
| `drop_dm_object_name("Processes")`
| `security_content_ctime(firstTime)`
|`security_content_ctime(lastTime)`
| `excel_spawning_powershell_filter`