As far as I can see what this code does is that it sends some basic user information to an external website and it may popup an alert window or open Safari or other apps based on the response of that external website.
It is not a compiler virus and there is nothing on how you can modify an XCode release to add the above into other developers' apps.
Nobody said it was. Modifying a compiler to inject XcodeGhost is simple assembly work. Almost anyone could figure it out in an afternoon.
Multiple independent security organizations are reporting that the modified XCode release was shared via a filesharing site in China. That is how so many Chinese iOS developers came across it.
The version of XcodeGhost on github is a harmless version posted by the original author. The actual compiled code being found in the wild has malicious abilities not found in the code in that GitHub repo.
http://security.tencent.com/index.php/blog/msg/96
Wrt. to this github:
https://github.com/XcodeGhostSource/XcodeGhost
As far as I can see what this code does is that it sends some basic user information to an external website and it may popup an alert window or open Safari or other apps based on the response of that external website.
It is not a compiler virus and there is nothing on how you can modify an XCode release to add the above into other developers' apps.