Techniques
Sample rules
Windows WSUS Spawning Shell
- source: splunk
- technicques:
- T1190
- T1505.003
Description
The following analytic identifies instances where a shell (PowerShell.exe or Cmd.exe) is spawned from wsusservice.exe, the Windows Server Update Services process. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where the parent process is wsusservice.exe. This activity is significant as it may indicate exploitation of CVE-2025-59287, a critical deserialization vulnerability in WSUS that allows unauthenticated remote code execution. If confirmed malicious, this behavior could allow attackers to execute arbitrary commands on WSUS servers, potentially leading to system compromise, data exfiltration, domain enumeration, or further lateral movement within the network.
Detection logic
| tstats `security_content_summariesonly` count values(Processes.process_name) as process_name values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name=wsusservice.exe AND `process_cmd` OR `process_powershell` by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_wsus_spawning_shell_filter`