Vanilla Forums 2.0.18.4 Tagging Stored XSS

                                                # Title: Vanilla Tagging Stored XSS
# Date: 1/6/12
# Author: Henry Hoggard
# Author URL: henryhoggard.co.uk
# Author Twitter: @henryhoggard
# Software: Vanilla Version 2.0.18.4
# http://vanillaforums.org/download

Create a new thread and post your XSS as tag. I used
<script>alert('xss')</script>

You will have to use a proxy / manipulate the form to bypass the max-length on the form.

Once you have posted the thread, send an administrator or moderator to

http://server/index.php?p=/vanilla/post/editdiscussion/7

Where 7 is the thread ID of the thread you just made. The XSS will then trigger.
You can even use a URL shortener to send the link.

Note: The URL may be different depending on what category your thread is in.

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