Suspicious Data Exfiltration Tool S3 Browser Execution (via process_creation)

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-07-05
Updated
2026-08-28

ATT&CK techniques

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. C2

  13. Impact

What it detects

This rule detects execution of the S3 Browser client, the third-party utility Muddled Libra uses to stage and exfiltrate collected data to attacker-controlled S3 buckets. Presence of S3 Browser on servers and admin hosts is abnormal and aligns with bulk cloud exfiltration after domain compromise.

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Suspicious Data Exfiltration Tool S3 Browser Execution (via process_creation)
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.