Suspicious Reflective Assembly Load in PowerShell (via ps_script)

ATT&CK techniques

Defense Evasion

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

What it detects

This rule detects PowerShell script content that reflectively loads a .NET assembly directly from a base64-decoded byte array. This in-memory loading technique was observed in the SHADOW#REACTOR campaign to execute a .NET Reactor protected loader.

Reporting behind it

Related detections9 linkedT1620 — drag to rearrange

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Suspicious PowerShell Reflective Assembly Load Invoking VAI Method (via process_creation)

PowerShell In-Memory Shellcode Execution via Memory Allocation APIs (via ps_script)

Suspicious Reflective Assembly Load in PowerShell (via ps_script)

Pivot detection · T1620 · 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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