Suspicious IIS Worker Process Spawning Whoami Reconnaissance

ATT&CK techniques

Persistence → Discovery

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
- T1033System Owner/User Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the IIS worker process w3wp.exe spawning whoami.exe, a webshell-driven reconnaissance behavior observed following exploitation of an internet-facing server. A web application context should never legitimately execute identity enumeration commands, so this parent-child relationship strongly indicates a deployed webshell running attacker commands. It typically marks the earliest hands-on-keyboard stage after initial access.

Reporting behind it

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Suspicious IIS Worker Process Spawning Whoami Reconnaissance

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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