Suspicious Kimsuky JS Downloader Staging in Public and Templates Paths (via file_event)

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects the creation of Kimsuky downloader and launcher scripts such as DefenderUpdate.js in Public Downloads or Templates.js and Templates.ps1 in the Windows Templates directory. These filenames and locations are used by the PebbleDash infection chain to stage follow on payloads.

Reporting behind it

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Suspicious Kimsuky JS Downloader Staging in Public and Templates Paths (via file_event)

Pivot detection · T1105 · 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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