Suspicious Quick Assist Remote Tool Launched by Explorer via Nimbus RAT Lure

PremiumReviewedSigma · Medium · v1
Category
process_creation
Author
HuntRule
Published
2026-09-22
Updated
2026-09-22

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 the Quick Assist remote assistance tool being launched from Explorer, the entry point in the Nimbus RAT campaign where actors impersonate IT support over Microsoft Teams. Attackers guide victims to start Quick Assist to gain hands-on-keyboard access before dropping the Java RAT. Because Quick Assist has legitimate support uses this warrants correlation with unexpected external sessions.

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Suspicious Quick Assist Remote Tool Launched by Explorer via Nimbus RAT Lure
Pivot detection · T1219 · 9 related

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