Malicious KoiLoader Persistence via Scheduled Task Running WScript

ATT&CK techniques

Execution → Priv Esc

Recon
Resource Dev
Initial Access
Execution
- T1053.005Scheduled Task
Persistence
- T1053.005Scheduled Task
Priv Esc
- T1053.005Scheduled Task
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the creation of a high-frequency scheduled task that launches WScript against a JavaScript file staged in ProgramData, the persistence mechanism used by KoiLoader. The one-minute recurrence combined with a script under ProgramData is characteristic of KoiLoader maintaining execution to fetch the KoiStealer payload.

Reporting behind it

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Malicious KoiLoader Persistence via Scheduled Task Running WScript

Pivot detection · T1053.005 · 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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