Archive for November, 2014

Those mysterious, fake cellphone towers popping up all over the U.S. : how they work

 

Fake cell towers

 

18 November 2014 – Back in August, reports started emerging of mysterious fake cellphone towers popping up all over the US. It led many to assume that there were actually strange towers of unknown purpose dotting the nation. The truth is these weren’t physical towers of any sort, but devices that were being made to trick your cellphone into thinking it was a tower.

Why would such a thing exist? There haven’t been any definitive answers, but the Wall Street Journal has reported that the answer may lie in a 7-year-old US Department of Justice program to track criminals via their cellphone, using devices attached to airplanes. The publication reported that sources wouldn’t confirm or discuss specifics about the program but did say these surveillance flights take place on a regular basis. The purpose is to track criminals and fugitives, but doing so requires a sweep that captures a lot of cellphone data from a given area. Once a suspect’s phone is found, the device releases the non-suspect phones.

Certainly news like this is going to fuel … Read more

81% of Tor users can be de-anonymized by analyzing router information, says researcher

 

Tor cartoon

15 November 2014 – A former researcher at Columbia University’s Network Security Lab has conducted research since 2008 indicating that traffic flow software included in network routers, notably Cisco’s ‘Netflow’ package, can be exploited to deanonymize 81.4% of Tor clients.

Professor Sambuddho Chakravarty, currently researching Network Anonymity and Privacy at the Indraprastha Institute of Information Technology, uses a technique which injects a repeating traffic pattern into the TCP connection associated with an exit node, and then compares subsequent aberrations in network timing with the traffic flow records generated by Netflow (or equivalent packages from other router manufacturers) to individuate the ‘victim’ client. In laboratory conditions the success rate of this traffic analysis attack is 100%, with network noise and variations reducing efficiency to 81% in a live Tor environment. Chakravarty says: “it is not even essential to be a global adversary to launch such traffic analysis attacks. A powerful, yet non- global adversary could use traffic analysis methods to determine the various relays participating in a Tor circuit and directly monitor the traffic entering the entry node of … Read more