Malicious Silver Fox PowerShell Download Cradle via irm and iex (via process_creation)

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
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects PowerShell combining Invoke-RestMethod with Invoke-Expression to download and directly execute remote content, the delivery cradle used by the Silver Fox ABCDoor campaign. The technique retrieves and runs backdoor code in memory following a tax themed phishing lure. Detecting the irm to iex pattern surfaces staged payload execution.

Reporting behind it

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Malicious Silver Fox PowerShell Download Cradle via irm and iex (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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