YesWiki before 4.6.7 contains an unauthenticated server-side request forgery vulnerability that allows remote attackers to make the server fetch arbitrary hosts and ports via the {{valeur}} actions url parameter. Attackers can submit the action through the content parameter of handlers/page/render.php to probe internal HTTP services and read back response content matching fiche markup.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.