Suspicious ToolShell Webshell Written to SharePoint Layouts Directory

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of the ToolShell webshell files spinstall0.aspx or ghostfile-prefixed .aspx files used by multiple threat actors after exploiting the SharePoint ToolShell vulnerability chain. These named ASPX payloads dropped onto a SharePoint server provide persistent remote command execution and are strong indicators of compromise.

Reporting behind it

Related detections9 linkedT1505.003 — drag to rearrange

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Suspicious ToolShell Webshell Written to SharePoint Layouts Directory

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.

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