Obfuscated XE Group Reflective Loader via PowerShell Spawned by IIS Worker Process (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1620Reflective Code Loading
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the IIS worker process w3wp.exe spawning a hidden PowerShell that runs a base64-encoded reflective loader, the in-memory execution step XE Group used after webshell access to launch Meterpreter. A web server process launching an obfuscated hidden PowerShell is a strong indicator of post-exploitation code execution.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

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Malicious Script Host Spawning PowerShell With Invoke-Expression (via process_creation)

Hidden PowerShell Archive Extraction via ExtractToDirectory

CastleLoader ClickFix PowerShell Hex Decode and Re-Execution

Malicious Non-Interactive Encoded PowerShell Stager (via process_creation)

Obfuscated XE Group Reflective Loader via PowerShell Spawned by IIS Worker Process (via process_creation)

Pivot detection · T1059.001 · 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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