source: https://www.securityfocus.com/bid/27878/info

SmarterMail is prone to an HTML-injection vulnerability because the application fails to properly sanitize user-supplied input.

Attacker-supplied HTML and script code would execute in the context of the affected site, potentially allowing the attacker to steal cookie-based authentication credentials or to control how the site is rendered to the user; other attacks are also possible.

SmarterMail Enterprise 4.3 is vulnerable; other versions may also be affected. 

<XSS STYLE="xss:expression(alert(&#039;1&#039;))"><XSS 
STYLE="xss:expression(alert(&#039;2&#039;))">