German researchers discover flaw that could let anyone listen to cell calls
There is a maintenance mode in every cell phone that allows it to be remotely turned on, that is, used as a listening device, without your knowledge.<p>I don't know what authentication is required.  I expect that it was designed so that only your cell carrier could enable it, however whatever may have been secret about it, quite likely has leaked out by now.<p>If you don't want to be listened-to, don't have _any_ cell phones anywhere near you.  Not just your own - say you want a private conversation in a public place; the phones of other people in your general vicinity could be switched on to listen to you.<p>I learned this from a well-known left-wing radical organization known as the United States Air Force, when I applied for the USAF Cyber Command.  Their site had a recruiting video, that depicted a couple officers locking their phones into a grounded metal box - a faraday cage - before entering a secure area, that is, a room where secrets were openly discussed.