"Mozilla is scrambling to patch a vulnerability in Firefox that is apparently being exploited in the wild to unmask Tor Browser users.
Earlier today, a small package of SVG, JavaScript and x86 code popped up on a Tor mailing list that, when opened by Firefox or Tor Browser on a Windows PC, phones home to a remote server and leaks the user's MAC address, hostname and potentially their public IP address. Typically, this exploit would be embedded in a webpage and leap into action when opened by an unsuspecting visitor."
http://www.theregister.co.uk/2016/11/30/possible_tor_browser_decloak_zero_day_dropped_patch_in_works/
https://web.archive.org/web/20161130072235/http://www.theregister.co.uk/2016/11/30/possible_tor_browser_decloak_zero_day_dropped_patch_in_works/
The malicious payload it delivers, according to an independent researcher who goes by the Twitter handle @TheWack0lian, is almost identical to one that was used in 2013 to deanonymize people visiting a Tor-shielded child pornography site. The FBI ultimately acknowledged responsibility for the exploit, which was embedded in Web pages served by a service known as Freedom Hosting.
http://arstechnica.com/security/2016/11/firefox-0day-used-against-tor-users-almost-identical-to-one-fbi-used-in-2013/
https://web.archive.org/web/20161130031656/http://arstechnica.com/security/2016/11/firefox-0day-used-against-tor-users-almost-identical-to-one-fbi-used-in-2013/
"This is an Javascript exploit actively used against TorBrowser NOW. It consists of one HTML and one CSS file, both pasted below and also de-obscured. The exact functionality is unknown but it's getting access to "VirtualAlloc" in "kernel32.dll" and goes from there. Please fix ASAP."
https://lists.torproject.org/pipermail/tor-talk/2016-November/042639.html
https://web.archive.org/web/20161130003501/https://lists.torproject.org/pipermail/tor-talk/2016-November/042639.html
[Editor's Note: The reporting only mentions Windows PCs, but it might not be limited to this OS.]
(Score: 0) by Anonymous Coward on Wednesday November 30 2016, @05:18PM
There is not yet enough analysis being made public for those using other OS to be feeling smug.
I'm an Apple user, smug is my natural state you insensitive clod!