Suspicious IIS Worker Process Spawning Command Shell via Web Shell (via process_creation)
- Category
- process_creation
- Author
- HuntRule
- Published
- 2026-07-08
- Updated
- 2026-08-28
ATT&CK techniques
Execution → PersistenceRecon
Resource Dev
Initial Access
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects the IIS worker process spawning a command interpreter or WMI utility, a behavior consistent with the Phantom Taurus web shell loading IIServerCore inside w3wp.exe. Server-side web shells use the worker process to execute reconnaissance and lateral movement commands. Detecting this chain surfaces active exploitation of a public-facing web application by a Chinese-nexus APT.
Reporting behind it
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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