MintsLoader AMSI Bypass via amsiInitFailed Reflection (via ps_script)

PremiumReviewedSigma · High · v1
Product
windows
Category
ps_script
Author
HuntRule
Published
2026-05-13
Updated
2026-08-28

ATT&CK techniques

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule detects the MintsLoader in-memory AMSI bypass that reflectively sets the amsiInitFailed field on the AmsiUtils type to disable the Antimalware Scan Interface before staging the next payload. Adversaries leverage this bypass to run malicious PowerShell content without scanning, making it a high-confidence defense-evasion indicator.

Related detections9 linkedT1685 — drag to rearrange
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Suspicious Windows Defender Real-Time Protection Disabled via Policy Registry by Cephalus Ransomware
Suspicious Microsoft Defender Path Exclusion of User Directories (via process_creation)
Malicious Windows Defender Tampering via Set-MpPreference (via process_creation)
Malicious Container Runtime Tampering via chmod on runc (via process_creation)
In-Memory AMSI or ETW Bypass in PowerShell (via process_creation)
Malicious Microsoft Defender Critical Security Components Disabled - Command (via process_creation)
Malicious Microsoft Defender Service Deactivation Attempt - Command (via process_creation)
Malicious Wdigest Authentication Enabled - Reg via Command (via process_creation)
MintsLoader AMSI Bypass via amsiInitFailed Reflection (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.