Suspicious Script Host Spawning PowerShell from Fake Browser Update JS

ATT&CK techniques

Execution

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

What it detects

This rule detects wscript or cscript executing a JScript file and spawning PowerShell, the delivery chain used by SmartApeSG fake browser update lures to pull a base64 encoded NetSupport payload. A JavaScript file launching PowerShell is a strong sign of a drive by download rather than legitimate scripting.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

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Windows AppLocker Audit-Mode Events Indicate Files Would Have Been Blocked

Windows AppLocker Blocked Application, Script, MSI, or Packaged-App Execution

Suspicious Script Host Spawning PowerShell from Fake Browser Update JS

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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