Malicious AMSI and ETW Bypass via In-Memory Patching (via ps_script)

ATT&CK techniques

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

What it detects

This rule detects PowerShell in-memory tampering with AMSI and ETW to blind endpoint defenses, used by the MIMICRAT loader. Observed in Elastic Security Labs analysis where amsiInitFailed forcing, EventProvider m_enabled zeroing, and ScanContent Marshal.Copy patching disable scanning and telemetry before staging the RAT.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious AMSI and ETW Bypass via In-Memory Patching (via ps_script)

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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