"Paros is a man-in-the-middle proxy and application vulnerability scanner. It allows users to intercept, modify and debug HTTP and HTTPS data on-the-fly between web server and client browser. It also supports client-certificate, proxy-chaining, filtering and various vulnerability scanning." - Paros

[New features]
" - Allow to run the scanner on a paticular request shown in the lower URL list (select the request on the URL list, right-click and choose 'Scan Selected Node/Item')
- Allow to re-send a paticular request shown in the lower URL list (select the request on the URL list, right-click and choose 'Re-send'). Check the correctness of the information such as the port before sending it out.
- Allow to craft a request by clicking the menu "Tools" => "Send HTTP(S) Requests"
- In the filter DetectUnsafeContent, add new IE vulnerability check, and improve ms-its checks and speed of other checks ."

Go to the main download page
Download the Source
Download the Windows Installer
Download the User Guide