On a multicore vulnerability

Sep 17, 2007 08:09 GMT  ·  By

It seems that a multicore computer may have a dangerous vulnerability that can lead to serious security problems. It is all based on concurrency, which is not a capacity that single core computers have. This great feature has been turned into a downfall, by researcher Robert Watson that showed how it could be exploited. For those of you that do not know, concurrency is the computer's power to handle two different processes at the same time. Multicore machines can handle more operations simultaneously. Such an example would be determining in which storage module the current instruction and the one that follows it are. Sounds complicated, but it sure raises computer performance!

In any case, when multicore was first built, they never thought there could be any interference in the process where the software interacts with the kernel (the nucleus of an operating system). But as the Register informs, Robert Watson showed that a carefully written exploit can attack in the little timeframe when this happens and alter the "communication" process. This is pretty severe, since using this vulnerability, a malicious user could bypass security software and become a serious threat.

The thing is that the kernel does not act blindly. Your computer doesn't do what you tell it to do and nothing else. When you try to access a file, first, it is tested to see if it does not pose a threat, and if it does, then an error message is displayed. This is called system call wrapping in techie tongue and it is used for kernel security. Now if this procedure gets bypassed, then you're in a whole world of trouble. If you are tech-savvy and you find an interest in these things, than you can read more about this exploit and how it works, by visiting this website.