http://www.neowin.net/forum/topic/1148702-realized-that-whatsapp-has-a-huge-security-flaw/ http://www.neowin.net/forum/topic/1148702-realized-that-what... I se

http://www.neowin.net/forum/topic/1148702-realized-that-whatsapp-has-a-huge-security-flaw/ http://www.neowin.net/forum/topic/1148702-realized-that-what... I seem to remember their authentication was a combination of your phone number and the IMEI of your handset, which is woeful security through obscurity at best.