LegionLoader Process Hollowing via SysWOW64 explorer.exe Self-Invocation (via process_creation)

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055.012Process Hollowing
Defense Evasion
- T1055.012Process Hollowing
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects explorer.exe launched with explorer.exe passed as its own argument, the anomalous invocation used by the LegionLoader shellcode to spawn a SysWOW64 explorer.exe target for process hollowing. Legitimate Windows shell launches never pass the binary name as a command-line argument, so this pattern surfaces the injection host before LegionLoader is mapped into memory.

Reporting behind it

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LegionLoader Process Hollowing via SysWOW64 explorer.exe Self-Invocation (via process_creation)

Pivot detection · T1055.012 · 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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