Monday, May 27, 2013

Bypassing the Corporate Proxy

This is a post in Spanish that explains how to bypass a corporate web proxy (and its filters) by using standard (not true 100%) Unix tools. In this scenario, the user wants to bypass a proxy (a Windows Proxy) that is using NTLM authentication in order to visit forbidden pages and/or for for privacy reasons.


The following tools are used:
  • cntlm is proxy that let our tools go through the proxy by doing the NTLM authentication bits. It will be listening in localhost and behaving like a common HTTP proxy.
  • corkscrew to tunnel SSH traffic over HTTP proxies
  • An ssh client to open a Socks proxy in localhost and an ssh server listening on 443.
  • A web browser that supports Socks proxies (e.g. Firefox)

The traffic will flow as follows:

Firefox -> ssh client -> corkscrew -> CNTLM -> Corporate Proxy -> SSH server -> Inet.

IPv6 security

This is a short video that discusses the security problems in IPv6, mainly DoS and MITM similar to the ones existing in IPv4. Unfortunately, the speaker doesn't introduce any tool for testing/pentesting our networks.

The talk discusses the problems found in the protocol and also exposes some extensions implemented in Cisco devices that may help to reduce the impact, even though they are not widely implemented in all platforms.

 The original source is SecDocs.