In case you missed it, the WASC Distributed Open Proxy Honeypot Project launched Phase III at the end of July. We have a few sensors online and as we start gathering data, we are starting our analysis. Our goal is to be able to release "events of interest" to the community to try and raise awareness of web-based attacks.
As part of my day job working with web application firewalls, I often get asked about why certain signatures should be applied in certain locations. Why not just apply signatures to parameter payloads? This would certainly cut down on potential false positives and also increase performance. While it is true that the most likely attack vector locations are parameter payloads, these are not the only ones. Where else should you look for attacks?
Well, in looking at the honeypot logs today, I noticed an interesting XSS attack vector - injecting the XSS code into the request User-Agent string. Here is an example of the captured data -
GET http://www.example.com/image-2707303-10559226 HTTP/1.1
Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, image/png, */*
Referer: http://www.example.co.uk/
Accept-Language: en-us
User-Agent: Mozilla/4.0 (compatible; MSIE6.0; Windows NT 5.1; SV1; . NET CLR 1.1.4322; <script>window. open('http://www.medchecker. t;/script>)com/side.htm ','_search')&l
Host: www.example.com
Connection: Keep-Alive