source: https://www.securityfocus.com/bid/44716/info
The jRSS Widget Plugin for WordPress is prone to an information-disclosure vulnerability because it fails to sufficiently validate user-supplied data.
An attacker can exploit this issue to view local files in the context of the affected application. This may allow the attacker to obtain sensitive information; other attacks are also possible.
jRSS Widget 1.1.1 is vulnerable; other versions may also be affected.
http://www.example.com/wordpress/wp-content/plugins/jrss-widget/proxy.php?url=../../../../../../../../windows/win.ini