Technology | GSM German Hacker Cracks Cell Phone Code Expert warns 80% of cell phones lack proper protection By Rob Quinn Posted Dec 30, 2009 4:36 AM CST Copied Confidential cell phone communications are at risk because the GSM algorithm has been compromised, hacker Karsten Nohl has warned. (AP Photo/Mark Lennihan) A German hacker says he and his team have managed to crack the code that has protected most of the world's cell phone conversations for over 20 years. Karsten Nohl told a hackers' conference in Berlin that cracking the encryption code for GSM communications—which secures 80% of cellular communications—raises serious security problems for phone networks, the Wall Street Journal reports. Cracking the GSM code previously required equipment costing hundreds of thousands of dollars, largely limiting spying to governments, Nohl told the conference. Armed with the code—which has been published online—criminals would have the capability to listen in on cell phone calls with a laptop and a couple of network cards. Nohl says he's not worried about lawsuits from phone companies because his research was undertaken purely to highlight security flaws and persuade companies to update their technology. Read These Next Trump has threatened to revoke Rosie O'Donnell's citizenship. FEMA failed to answer thousands of calls after the Texas floods. Newsom turns nickname back on Trump. Air India pilots cut off fuel to engines 30 seconds into flight. Report an error