Malicious Dropbox Cloud C2 via Spoofed Googlebot User Agent

PremiumReviewedSigma · High · v1
Category
proxy
Author
HuntRule
Published
2026-10-16
Updated
2026-10-16

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 web traffic to the Dropbox content API using a spoofed Googlebot user agent which the RokRat implant used for command and control as analysed by NCC Group. Abusing a legitimate cloud storage API with a crawler user agent lets the malware blend exfiltration and tasking into normal web traffic.

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Malicious Dropbox Cloud C2 via Spoofed Googlebot User Agent
Pivot detection · T1071.001 · 9 related

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