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

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1219Remote Access Tools
Exfiltration
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.

Reporting behind it

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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.

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