huntrule

Suspicious AddInProcess32 Outbound Connection after Process Hollowing

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

ATT&CK techniques

Priv Esc → C2

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule detects the dotnet AddInProcess32 utility initiating outbound network connections which is highly unusual. Ande Loader hollowed 0bj3ctivity Stealer into AddInProcess32 so its C2 and exfiltration traffic run under a signed process. External connections from this rarely used binary indicate injected stealer activity.

Reporting behind it

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Suspicious AddInProcess32 Outbound Connection after 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.