yahoomail dom based xss vulnerability

[pratul agrawal <pratulag () yahoo com>]

Yahoo mail Dom Based Cross Site 
Scripting

                     Founder: Pratul Agrawal <pratulag[at]yahoo[dot]com>
DescriptionService: Webmail



Vendor: Yahoo mail, and possibly others



Vulnerability: Cross Site Scripting / Cookie-Theft / Relogin attacks



Severity: High



Tested on: Microsoft IE 7.0



Details:



Yahoo mail filter fails to detect script attributes in combination with

the style attribute as a tag, leaving everyone using yahoo mail service

with MSIE vulnerable to Cross Site Scripting including Cookie Theft and

relogin attacks.



Impact:



This is totally a dom based xss attack. an application takes the user 
suplied data and directly feed it into the API designed to show the 
Newly created folder name n the yahoomail. Throug this an attacker can 
easily perform a cookie theft attack, Site defacement attack and many 
more.Steps To 
Reproduce1. Login the yahoomail with 
valid credentials.

 

2. Click on inbox.

 

3. Now click on Move < [New Folder].

 

4. Now enter the javascript "><script>alert('yahoo')</script> in the field given for creating new folder.

 

5. Press OK and the script get executed.  yahhhhooooo
Best Regards,
Pratul Agrawal


_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/