Two major defects have recently emerged in such well-known, used and popular systems as the Skype and even all Apple products. A simple text message can literally crash apps and even devices. Let’s get a bit deeper, ok?
So, there is this 75-byte Unicode sequence that consists of several Arabic, and Hindi letters and other symbols that triggers a really curtail glitch. I will not be writing the actual message here due lots of damage was already done (but you can still look it up in Google, it’ll probably appear to you from the very first search result).
So when this very text appears on the notification screen iStuff crashes. If you text it to a friend their device will force-reboot. Repeatedly, at some times. If we are interested in closer defect details, it initiates a string of events in Apple’s own CoreText library thus OS X is as valuable as iOS systems. User log in’s may be crashed if the sequence is input in the server/etc/motd for example, due the Terminal will be crashed.
It’s not the characters from different languages that matter, it’s the Unicode they represent and the way CoreText processes it. When the Unicode is processed, CoreText will access invalid memory, thus OS is forced to kill any program which is currently running (in can be your terminal, text message app, etc.) and, if the notification screen is the case core OS parts will be forced to shut down, thus ending up crashed.
This defect is somehow similar to the previously described one. If characters “http://:” are sent into a group chat any person receiving the message will face a crashed Skype app and the same error will commence every time such a person will try to log in. A repeated cycle of crashes during login will continue until the app is deleted or degraded to an older version.
This defect works fine on almost all OSs, like Windows, iOS and Android, however has no effect on Macs and the Metro app. For now, one of the best solutions is downgrading Skype to 126.96.36.199 version helps, and Skype officials have stated that they are currently working on a fix.
Where am I headed to with this?
Both defects were spotted and reported by users, the Apple defect was firs described on Reddit, and Skype user “Giperion” has located the second bug. Both of these defects were missed while testing was on.
But does this mean testers did a terrible job? Well, no, it does not. These defects only prove that it’s impossible to detect and fix every single bug in the code. I mean, what were the odds somebody would text a message with a random combo of Hindi, Arabic and other symbols? But we all should still try harder, though.