Showing posts with label hacking. Show all posts
Showing posts with label hacking. Show all posts

Thursday, July 28, 2016

Intercepting SSL and more with WPAD

This morning I read Sniffing HTTPS URLS with malicious PAC files by Alex Chapman and Paul Stone. It's an excellent summary of a key problem with PAC files, mainly that its a JavaScript file delivered by HTTP with well-known techniques to push to unsuspecting clients, and that this script has full access to all URLs - including the content of SSL URLs. Chapman and Stone demonstrate a simple technique to exfiltrate the SSL URLs via DNS. Since the technique is now public, I'm publishing my findings and code from 2007 as a more fully weaponized tool that allows selective targeting and exfiltration of URL (including SSL URL) values.

Tuesday, August 6, 2013

Challenger: A Tool for Breaking NETNTLM/MSCHAP Hashes


A few months ago I stumbled upon an excellent write-up explaining the details of NETNTLM (NTLMv1 Challenge Response) authentication. It's an interesting design, and two things jumped out at me right away: the use of a symmetric cipher (DES) rather than only hashing functions, and the odd way the hash is split into three, uneven, portions. This inspired me to work on increased attack speeds against NETNTLM. In the end, I created a small Python tool called Challenger that significantly accelerates dictionary-based attacks on NETNTLM challenge-response hashes.