Suspicious PowerShell Download Of Text-Disguised Payload

ATT&CK techniques

Defense Evasion → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects PowerShell downloading a file with a .txt extension using a web download method. MoonPeak loaders retrieved a calc.txt file that was actually a GZIP-compressed RTF payload staged for later conversion and execution. Serving executable or archive content under an innocuous .txt name is a masquerading trick used to slip payloads past content filters.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange

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Suspicious PowerShell Download Of Text-Disguised Payload

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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