Suspicious winhlp32 Network Connection Indicating RemcosRAT Injection

PremiumReviewedSigma · High · v1
Product
windows
Category
network_connection
Author
HuntRule
Published
2026-07-06
Updated
2026-08-28

ATT&CK techniques

Priv Esc → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects winhlp32.exe establishing an external network connection, behavior the legacy help viewer never performs and used in the OnlyDcRatFans intrusion as the injection host for RemcosRAT command and control. An outbound connection from winhlp32 signals injected malicious code beaconing to an attacker server.

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Suspicious winhlp32 Network Connection Indicating RemcosRAT Injection
Pivot detection · T1055 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.