Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
- T1059.007JavaScript
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects wscript.exe or cscript.exe executing a .js file and spawning PowerShell with an encoded command. The Emmenhtal loader used in this MaaS operation against Ukrainian entities runs JavaScript such as Work.js via WScript.Shell to launch encoded PowerShell that fetches the Amadey payload, so this script-to-encoded-PowerShell chain is the core delivery behavior.

Reporting behind it

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Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell

Pivot detection · T1059.001 · 9 related

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