A tool that will do a man-in-the-middle attack on SSL connections and, if vulnerable, exploit the BasicConstraints Internet Explorer vulnerability.
This tool was originally written to demonstrate and exploit IE's vulnerability to a specific "basicConstraints" man-in-the-middle attack. While Microsoft has since fixed the vulnerability that allowed leaf certificates to act as signing certificates, this tool is still occasionally useful for other purposes.
It is designed to MITM all SSL connections on a LAN and dynamically generates certs for the domains that are being accessed on the fly. The new certificates are constructed in a certificate chain that is signed by any certificate that you provide.
Version 0.6 has been significantly updated to additionally support the null-prefix attacks that I demonstrated at BlackHat 09 and Defcon 17. These allow for completely silent MITM attacks against SSL/TLS in the NSS, Microsoft CryptoAPI, and GnuTLS stacks — ultimately allowing for SSL communication in Firefox, Internet Explorer, Chrome, Thunderbird, Outlook, Evolution, Pidgin, AIM, irssi, and every other client that uses the Microsoft CryptoAPI to be intercepted.
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