CastleLoader ClickFix PowerShell Hex Decode and Re-Execution

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a ClickFix style command that decodes a hex encoded string in PowerShell and pipes the result into a second PowerShell instance for execution. This pattern delivers CastleLoader and related payloads directly in memory.

Reporting behind it

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CastleLoader ClickFix PowerShell Hex Decode and Re-Execution

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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