Anatomy of a killer bug: How just 5 characters can murder iPhone, Mac apps

There has been much sniggering into sleeves after wags found they could upset iOS 6 iPhones and iPads, and Macs running OS X 10.8, by sending a simple rogue text message or email.

A bug is triggered when the CoreText component in the vulnerable Apple operating systems tries to render on screen a particular sequence of Unicode characters: the kernel reacts by killing the running program, be it your web browser, message client, Twitter app or whatever tried to use CoreText to display the naughty string.

Much hilarity ensued as people tweeted the special characters, posted them in web article comments or texted them, and rejoiced in the howls of fanbois' frustration. (Facebook had to block the string from being submitted as a status update.)