What I found to be most troubling is the possibility that this could get used for breaking out of a VM and reading the memory of the host machine. If true, an attacker could simply rent space on a rackmount server and run whatever code they wanted, so that it was able to retrieve kernel memory from the other VMs on the same host. It's only mentioned in passing here, and it seems like speculation by the way they're phrasing it. But scary.