Suspicious Outbound Request to Webhook.site Interaction Service

PremiumReviewedSigma · Medium · v1
Category
process_creation
Author
HuntRule
Published
2026-09-29
Updated
2026-09-29

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 curl.exe issuing a request to webhook.site, an out-of-band interaction service Huntress observed being used to confirm code execution and beacon after Wing FTP CVE-2025-47812 exploitation. Attackers rely on webhook.site to receive callbacks and stage small amounts of exfiltrated data over a trusted domain. Outbound requests to this service from a server process are a suspicious command-and-control indicator.

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Suspicious Outbound Request to Webhook.site Interaction Service
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.