Malicious alexantr File Manager Webshell Access after CraftCMS Compromise (via webserver)

PremiumReviewedSigma · High · v1
Category
webserver
Author
HuntRule
Published
2026-08-30
Updated
2026-08-30

ATT&CK techniques

Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects requests to a filemanager.php webshell with its upload and delete parameters, the open-source alexantr file manager dropped to the web root following CraftCMS CVE-2025-32432 exploitation. Adversaries use this webshell to browse, upload and remove files on the compromised server for hands-on-keyboard actions.

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Malicious alexantr File Manager Webshell Access after CraftCMS Compromise (via webserver)
Pivot detection · T1505.003 · 9 related

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