Malicious HarborWatch RAT Command and Control Beacon by User Agent (via proxy)

PremiumReviewedSigma · High · v1
Category
proxy
Author
HuntRule
Published
2026-09-12
Updated
2026-09-12

ATT&CK techniques

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. Exfiltration

  13. Impact

What it detects

This rule detects outbound HTTP requests carrying the HarborWatchAgent user agent string used by the custom monitoring RAT delivered through a fake Amazon ClickFix lure. This hardcoded agent value is specific to the malware and should not appear in normal traffic.

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Malicious HarborWatch RAT Command and Control Beacon by User Agent (via proxy)
Pivot detection · T1071.001 · 9 related

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