Microsoft SharePoint SSI / ViewState Remote Code Execution
Posted on 19 October 2020
This Metasploit module exploits a server-side include (SSI) in SharePoint to leak the web.config file and forge a malicious ViewState with the extracted validation key. This exploit is authenticated and requires a user with page creation privileges, which is a standard permission in SharePoint. The web.config file will be stored in loot once retrieved, and the VALIDATION_KEY option can be set to short-circuit the SSI and trigger the ViewState deserialization.
