Research and Development

pass-the-hash

FreeRDP-pth is a slightly modified version of FreeRDP that tries to authenticate using a password hash instead of a password.  This work only against RDP v8.1 servers (Windows 2012 R2 at the time of writing) and even then, only for members of the administrators groups. Continue reading →

Windows 2012 R2 servers use a newer version of the Remote Desktop Protocol (RDP) that has a feature that will be interest to both penetration testers and system administrators.  This post describes the new “Restricted Admin” feature, the security benefits it brings and a potential downside of the feature: Pass-the-Hash attacks.  We’ll briefly recap what Pass-the-Hash attack are and demonstrate such an attack against a Windows 2012 R2 server. A proof-of-concept (PoC) tool to carry out Pass-the-Hash attacks against Windows 2012 R2 server is also released – a trivial modification to the excellent FreeRDP client. Continue reading →