Suspicious Hidden PowerShell Retrieving VBScript from mcdir.me by Millenium RAT (via process_creation)

ATT&CK techniques

Execution

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
- T1204.002Malicious File
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects hidden PowerShell fetching a VBScript stager from the mcdir.me delivery host used in the Millenium RAT malware-as-a-service infection chain launched from a malicious LNK. The script downloads and runs the next-stage executable while showing the victim a decoy PDF. Detecting the download cradle interrupts the RAT installation early.

Reporting behind it

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Suspicious Hidden PowerShell Retrieving VBScript from mcdir.me by Millenium RAT (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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