Suspicious Payload Download to Temp Masquerading as System32 File (via process_creation)

ATT&CK techniques

Defense Evasion → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects PowerShell using Invoke-WebRequest to save a payload into the temp directory under a system32 style filename. OneNote delivered malware wrote files such as system32.exe and system32.bat into the user temp path to blend in before launching them.

Reporting behind it

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Suspicious Payload Download to Temp Masquerading as System32 File (via process_creation)

Pivot detection · T1105 · 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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