Suspicious PowerShell Communication with Dropbox API (via ps_script)

PremiumReviewedSigma · Medium · v1
Product
windows
Category
ps_script
Author
HuntRule
Published
2026-06-05
Updated
2026-08-28

ATT&CK techniques

C2 → Exfiltration
  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. Impact

What it detects

This rule detects PowerShell script content that contacts the Dropbox content API file download endpoint. The DEEP#GOSU campaign abused Dropbox as a staging and exfiltration channel for encrypted payloads and stolen data.

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Malicious Data Exfiltration via Renamed Rclone Using Masqueraded Configuration
Suspicious Cloud Exfiltration via Rclone
Suspicious Rclone Cloud Sync Execution for Data Exfiltration via Command Line
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Suspicious PowerShell Communication with Dropbox API (via ps_script)
Pivot detection · T1567.002 · 9 related

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