Connect2 Cross-site Scripting

** DISPUTED ** Lorensbergs Connect2 3.13.7647.20190 is affected by an XSS vulnerability. Exploitation requires administrator privileges and is performed through the Wizard editor of the application. The attack requires an administrator to go into the Wizard editor and enter an XSS payload within the Page title, Page Instructions, Text before, Text after, or Text on side box. Once this has been done, the administrator must click save and finally wait until any user of the application performs a booking for rental items in the booking area of the application, where the XSS triggers. NOTE: another perspective is that the administrator may require JavaScript to customize any aspect of the page rendering. There is no effective way for the product to defend users in the face of a malicious administrator. (2022-01-12, CVE-2021-43960)

Cross site scripting is an attack where a web page executes code that is injected by an adversary. It usually appears, when users input is presented. This attack can be used to impersonate a user, take over control of the session, or even steal API keys.

The attack can be executed e.g. when you application injects the request parameter directly into the HTML code of the page returned to the user:

https://server.com/confirmation?message=Transaction+Complete

what results in:

<span>Confirmation: Transaction Complete</span>

In that case the message can be modified to become a valid Javascript code, e.g.:

https://server.com/confirmation?message=<script>dangerous javascript code here</script>

and it will be executed locally by the user's browser with full access to the user's personal application/browser data:

<span>Confirmation: <script>dangerous javascript code here</script></span>