Suspicious Child Process Spawned by IIS Worker w3wp

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the IIS worker process w3wp.exe spawning PowerShell, cmd, or certutil, the webshell execution pattern seen in WS_FTP exploitation. The IIS worker should serve web content, not launch interactive shells or download tools, so these children indicate server-side code execution through a web application compromise.

Reporting behind it

Related detections9 linkedT1505.003 — drag to rearrange

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Suspicious Child Process Spawned by IIS Worker w3wp

Pivot detection · T1505.003 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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