Malicious Powerfun Reverse Shell Script via Script Block (via ps_script)

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 execution of the powerfun PowerShell reverse shell, the interactive backdoor deployed over port 443 after FortiClientEMS exploitation as documented by Red Canary. Powerfun is a publicly available offensive script with no legitimate use, so any script block referencing it indicates hands-on-keyboard remote access.

Reporting behind it

Related detections9 linkedT1071.001 — drag to rearrange

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Suspicious PowerShell Web Request to oastify Out-of-Band Domain

Suspicious PowerShell Spawned by Web Browser

Suspicious PowerShell Interaction with ProgramData SysInt Log via Process Creation

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

Suspicious PowerShell COM-Based Script Execution and HTTP Retrieval (via ps_script)

Suspicious PowerShell Stager Download of Spf Script by Seedworm

Windows curl.exe SOCKS Proxy and .onion Command-Line Execution

Malicious Data Exfiltration via curl with Stealer Specific BuildID Header

Malicious Powerfun Reverse Shell Script via Script Block (via ps_script)

Pivot detection · T1071.001 · 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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