Suspicious PEAKLIGHT Memory-Only PowerShell Downloader Flags (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects PowerShell launched with the hidden window, unrestricted execution policy and no-profile flag combination used by the PEAKLIGHT downloader to fetch and AES-decrypt a memory-resident payload. This flag stacking is characteristic of obfuscated fileless staging.

Reporting behind it

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Suspicious PEAKLIGHT Memory-Only PowerShell Downloader Flags (via process_creation)

Pivot detection · T1027 · 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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