Suspicious SearchIndexer Process Started by Non-Service Parent for Hollowing

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-21
Updated
2026-09-21

ATT&CK techniques

Priv Esc → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects SearchIndexer.exe launched by a parent other than services.exe, an anomaly SolarMarker creates when hollowing the Windows search binary to host its payload. Legitimately SearchIndexer is started only by the service control manager. Detecting an unexpected parent exposes code injection into a trusted process.

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Suspicious SearchIndexer Process Started by Non-Service Parent for Hollowing
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.