Suspicious ffuf Fuzzing Requests Against Web Server

PremiumReviewedSigma · Medium · v1
Category
webserver
Author
HuntRule
Published
2026-09-19
Updated
2026-09-19

ATT&CK techniques

Recon → Initial Access
  1. Resource Dev

  2. Execution

  3. Persistence

  4. Priv Esc

  5. Defense Evasion

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects web requests carrying the ffuf fuzzer user agent or its FUZZ placeholder marker as covered in Elastic research on detecting web server probing in Traefik. These requests represent active directory and parameter brute forcing used to enumerate hidden endpoints before exploitation.

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Suspicious ffuf Fuzzing Requests Against Web Server
Pivot detection · T1190 · 9 related

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