------------------------------------------------------------------------ Cross-Site Scripting vulnerability in Quotes Collection WordPress Plugin ------------------------------------------------------------------------ Yorick Koster, July 2016 ------------------------------------------------------------------------ Abstract ------------------------------------------------------------------------ A Cross-Site Scripting vulnerability was found in the Quotes Collection WordPress Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. In order to exploit this issue, the attacker has to lure/force a logged on WordPress Administrator into opening a malicious website. ------------------------------------------------------------------------ OVE ID ------------------------------------------------------------------------ OVE-20160712-0015 ------------------------------------------------------------------------ See also ------------------------------------------------------------------------ Plugin Vulnerabilities [2] - Reflected Cross-Site Scripting (XSS) Vulnerability in Quotes Collection ------------------------------------------------------------------------ Tested versions ------------------------------------------------------------------------ This issue was successfully tested on Quotes Collection [3] WordPress Plugin version 2.0.5. ------------------------------------------------------------------------ Fix ------------------------------------------------------------------------ There is currently no fix available. ------------------------------------------------------------------------ Introduction ------------------------------------------------------------------------ The Quotes Collection [3] WordPress Plugin with Ajax powered Random Quote sidebar widget helps you collect and display your favourite quotes in your WordPress website. A Cross-Site Scripting vulnerability was found in the Quotes Collection WordPress Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. In order to exploit this issue, the attacker has to lure/force a logged on WordPress Administrator into opening a malicious website. ------------------------------------------------------------------------ Details ------------------------------------------------------------------------ The issue exists in the file class-quotes-collection-admin.php and is caused by the lack of output encoding on the page request parameter. The vulnerable code is listed below.
search_box( __('Search', 'quotes-collection'), 'quotescollection'); ?>
display(); ?>
Normally, the page URL parameter is validated by WordPress, which prevents Cross-Site Scripting. However in this case the value of page is obtained from $_REQUEST, not from $_GET. This allows for parameter pollution where the attacker puts a benign page value in the URL and simultaneously submits a malicious page value as POST parameter. ------------------------------------------------------------------------ Proof of concept ------------------------------------------------------------------------
------------------------------------------------------------------------ References ------------------------------------------------------------------------ [1] https://sumofpwn.nl/advisory/2016/cross_site_scripting_vulnerability_in_quotes_collection_wordpress_plugin.html [2] https://www.pluginvulnerabilities.com/2016/09/13/reflected-cross-site-scripting-xss-vulnerability-in-quotes-collection/ [3] https://wordpress.org/plugins/quotes-collection/