Update: 13th April 2016:
Further details as well as updates to resolve the Badlock issue are discussed in a more recent blog post.
Earlier this week an announcement was made by SerNet (a Samba consulting company who set up the Badlock website) that a critical security update would be made available on the 12th of April to address a vulnerability in the SMB/CIFs protocol (defined below) that is the basis of the open source Samba project. The 12th of April is the well-known second Tuesday of the month known as Update Tuesday (or Patch Tuesday) when Adobe, Microsoft and others commonly make available security updates on a scheduled basis.
Some advice that you can follow to better prepare for this update being made available is described in this SANS blog post as well as this very informative and practical InfoWorld article. Further background on this announcement can be found here.
I will publish another blog post on or very soon after the 12th of April to provide the appropriate information for you to address this vulnerability in a timely manner.
What is the SMB/CIFS protocol?
The Server Message Block (SMB) protocol is also referred to as the Common Internet File System (CIFS) is an application layer (layer 7 of the OSI model) protocol that allows the sharing of printers but mainly provides file access/transfer in a Microsoft network using mapped network drives. Further features of SMB/CIFS are detailed in this Sophos blog post.
Samba is an open source (the source code (human readable code) is free to view and edit by the wider IT community) application that provides the above mentioned network services across Linux/Unix and Microsoft servers/clients.