Suspicious In-Memory PowerShell Execution from Web Server via Automation Assembly (via image_load)

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects an IIS worker process loading the System Management Automation assembly, which enables PowerShell execution without launching powershell.exe. Weaver Ant used this technique from a web shell to run PowerShell in memory while evading process based detection. Web server worker processes do not normally load this assembly.

Reporting behind it

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Suspicious In-Memory PowerShell Execution from Web Server via Automation Assembly (via image_load)

Pivot detection · T1685 · 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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