Suspicious SearchProtocolHost Network Connection Indicating Process Hollowing

PremiumReviewedSigma · High · v1
Product
windows
Category
network_connection
Author
HuntRule
Published
2026-09-20
Updated
2026-09-20

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 SearchProtocolHost.exe initiating an external network connection, behavior inconsistent with the Windows Search indexer and used by Pikabot as a process hollowing target for command and control. The indexer never reaches out to the internet, so an outbound connection from it points to injected malicious code.

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Suspicious SearchProtocolHost Network Connection Indicating Process 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.