Equation: The Death Star of Malware Galaxy https://securelist.com/blog/research/68750/equation-the-death-star-of-malware-galaxy/ reported to compromise the firmware of hard drive and reprogram the hard drive's firmware according to Malware instructions. This seem to be a vulnerability and probable compromise for Tor browser usage, given it most likely use the hard drive on the computer. But how much vulnerability does Tails encounter and what is the probability of Tails compromise with this Malware?
Update: Following information became available recently:
http://www.scribd.com/doc/255979726/Equation-Group-Questions-and-Answers
http://www.forbes.com/sites/thomasbrewster/2015/02/16/nsa-equation-cyber-tool-treasure-chest/
https://en.wikipedia.org/wiki/Equation_Group
http://foreignaffairs.co.nz/2015/02/17/equation-the-death-star-of-malware-galaxy/
http://www.wired.com/2015/02/kapersky-discovers-equation-group
http://boingboing.net/2015/02/16/shining-light-on-the-shadowy.html
http://www.i4u.com/2015/02/88843/kaspersky-uncovers-most-sophisticated-malware
http://www.net-security.org/malware_news.php?id=2966
http://motherboard.vice.com/tag/Equation+Group