Tar archive won't unpack – "Path contains '..'"

You'll want to add the P (or -P) flag to your command line. From the manpage:

-P Preserve pathnames. By default, absolute pathnames (those that begin with a / character have the leading slash removed both when creating archives and extracting from them. Also, tar will refuse to extract archive entries whose pathnames contain .. or whose target directory would be altered by a symlink. This option suppresses these behaviors.

Try tar Pxvf 2014-12-12\ 04-00-01.tar. Note that you'll need write access to the parent directory of the working directory where you invoke the command.

You could try:
mkdir ./dir
tar xvf 2014-12-12\ 04-00-01.tar -C --./dir