A court filing has revealed claims by the FBI that it cloned an entire server belonging to anonymous email service Tor Mail, which likes to portray itself as an untrackable web tool.
The filing made reference to a warrant the FBI attained in summer 2013 that allowed it access to Tor Mail's servers while following up a case involving an alleged child abuse material distributor who was believed to be using the service.
After gaining access, the US postal inspector who submitted the filing reported that the FBI "obtained a copy of a computer server located in France via a Mutual Legal Assistance Treaty request to France, which contained data and information from the Tormail email server, including the content of Tormail email accounts".
While it's unclear how much user data resided in this server, the data collection is known to cover all users, meaning potentially any users of the anonymized service could find themselves at risk of having their data accessed by the FBI.
Tor Mail has already struck back, adding a message to its homepage saying, "We have no information to give you or to respond to any subpeona's [sic] or court orders. Do not bother contacting us for information on, or to view the contents of a Tor Mail user inbox, you will be ignored."
The FBI does not appear to have directly used the data to make specific prosecutions – yet.