With just the telephone number to go on, it is possible to track the location of a Danish mobile phone with relative ease – a breach that could foreseeably be exploited by private companies and foreign and domestic security agencies.

This was the result of a series of tests undertaken for the newspaper Information. Karsten Nohl, who is the head of research at the IT security firm SRLabs, conducted the tests for the newspaper. “TDC reveals fairly accurately the precise location of the telephone using a telephone number,” he said.

TDC aware of problem
The German IT consultant, working remotely from his own country, was able to determine that a telephone, belonging to Information and connected to the TDC network, was in the locality of Dronning Louises Bro in central Copenhagen.

Nohl’s assessment is that the majority of phones on the TDC network are equally vulnerable to tracking. He identifies a smaller risk with phones on the 3 Network.

TDC acknowledged to Information that the company was aware of the problem. “We are working on two concrete solutions. But we don’t wish to go into the details of these with the media,” the company said.