That's my question as well. I'm not a security expert, but this doesn't seem all that concerning for anything other then the highest security applications. It seems to me that executing this attack not only requires running code on the target machine (which admittedly isn't that big of a hurdle), but requires basically complete knowledge of memory allocation at the time of the attack, something that is fairly opaque and ever changing on most hardware.

Is there something I'm missing here? What are the realistic attacks that this vulnerability allows?