Suspicious PowerShell Invoke-WebRequest Piped to Invoke-Expression via FakeBat Loader

ATT&CK techniques

Execution → C2

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects PowerShell downloading a remote payload with Invoke-WebRequest using a custom User-Agent and piping the response straight into Invoke-Expression. FakeBat, also tracked as EugenLoader, delivers this one liner through malvertising and fake software sites to stage its next component in memory. Fileless download and execute cradles like this bypass disk based controls and warrant investigation.

Reporting behind it

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Suspicious PowerShell Invoke-WebRequest Piped to Invoke-Expression via FakeBat Loader

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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