Suspicious File Write to SharePoint Layouts Directory (via file_event)

This rule detects anomalous file writes to SharePoint layouts directory which could indicate webshell behavior or post-exploitation. This behavior has been observed in the exploitation of SharePoint vulnerabilities such as CVE-2025-49704, CVE-2025-49706 or CVE-2025-53770.

SigmahighWindowsv1
Full detection rule

Unlock this rule to view and copy it

Rule logic is available with an unlock credit. The public page keeps its context, mappings and implementation details visible.

Sign in to unlock

Known false positives

  • Unknown

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