Suspicious PowerShell Reading Base64 Payload from MI_V Environment Variable via process_creation

ATT&CK techniques

Execution

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

What it detects

This rule detects PowerShell referencing the MI_V or MI_V2 environment variables that the Argamal RAT uses to stage base64 encoded script payloads. Passing encoded stages through custom environment variables hides the command line and defeats simple string logging. This staging pattern is a strong execution and obfuscation indicator.

Reporting behind it

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Suspicious PowerShell Reading Base64 Payload from MI_V Environment Variable 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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