source: https://www.securityfocus.com/bid/12358/info

Exponent is reported prone to multiple cross-site scripting vulnerabilities.

An attacker may leverage these issues to have arbitrary script code executed in the browser of an unsuspecting user facilitating theft of cookie-based authentication credentials and other attacks.

Exponent 0.95 is reported prone to these issues. It is likely that previous versions are vulnerable as well. 

http://www.example.com/endon/mod.php?action=[BLABLA]&module=[XSS]
http://www.example.com/expo/index.php?action=createuser&module=%3Cscript%3Ealert(document.cookie)%3C/script%3E
http://www.example.com/expo/index.php?action=view&id=2&module=<h1>Tes</h1>