source: https://www.securityfocus.com/bid/64779/info

Atmail Webmail Server is prone to an HTML-injection vulnerability.

Successful exploits will allow attacker-supplied HTML and script code to run in the context of the affected browser, potentially allowing the attacker to steal cookie-based authentication credentials or control how the site is rendered to the user. Other attacks are also possible.

Atmail 7.1.3 is vulnerable; others versions may also be affected. 

 <iframe width=0 height=0 src="javascript:alert('xss in main body')">