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

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055Process Injection
Defense Evasion
- T1055Process Injection
- T1620Reflective Code Loading
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a PowerShell script block that combines GlobalAlloc VirtualProtect and CreateThread calls to allocate executable memory and run shellcode, the in-memory loading behavior of the RokRAT search.dat loader read from the public directory. Adversaries leverage reflective shellcode execution to run their payload without touching disk as a file, making early detection critical for surfacing fileless code execution before RokRAT deploys.

Reporting behind it

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

Pivot detection · T1055 · 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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