Malicious SharePoint spinstall0 Webshell Dropped in LAYOUTS
- Product
- windows
- Category
- file_event
- Author
- HuntRule
- Published
- 2026-07-11
- Updated
- 2026-08-28
ATT&CK techniques
PersistenceRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects the spinstall0.aspx file being written into the SharePoint LAYOUTS directory. Attackers exploiting the ToolShell chain drop this ASPX webshell to steal machine keys and maintain access. Creation of spinstall0.aspx in LAYOUTS is a definitive post-exploitation indicator.
Reporting behind it
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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