The design flaw would eventually allow malicious programs to access protected areas of kernel memory, which basically is the home of all the essential core components of an OS and its interactions with the hardware. What’s even more disturbing is the fact that this flaw can expose sensitive, protected information like passwords. The flaw is present in the Intel x86-64 hardware and requires an OS-level overwrite on every mainstream OS being patched.
The report, published in The Register, states that the bug may lead to grave consequences if OS kernel patches are not released for Windows, Linux and OS X. It must be noted that multiple generations of Intel CPUs are affected by this flaw.
However, the fixes would lead to affecting the performance of CPUs as these would become slower than usual so there are chances that your gaming experience on PC would be affected slightly but not entirely. As identified by researchers, “5 to 30 percent slowdown, depending on the task and processor model” is expected to hit CPUs due to the flaw.
The attack method involves identifying virtual memory pages in certain sequences in order to reveal memory locations where protected kernel space is present. Since this is a hardware bug, therefore, it is difficult to fix it unless Intel issues a fix in the next generation of CPUs.
As of now, the exact details of the design flaw and the extent to which it makes users vulnerable are kept hidden but it is evident that developers are in a rush to release patches, which hints upon the gravity of the situation.
In its Monday blog, the Python Sweetness wrote: “Urgent development of a software mitigation is being done in the open and recently landed in the Linux kernel and a similar mitigation began appearing in NT kernels in November. In the worst case, the software fix causes huge slowdowns in typical workloads … There are hints the attack impacts common virtualization environments including Amazon EC2 and Google Compute Engine.”
A short-term fix would be from the OSes, that is, operating systems can apply a kernel Page Table Isolation (PTI) to hide kernel memory addresses. This will force the processor to continually flush its caches holding TLBs.
A PMTS software engineer at AMD, Thomas Lendacky, stated that AMD CPUs are not affected by this bug and that the PTI patch will not be enabled on them because its memory controller doesn’t allow the same memory references that let fewer privileges calls to access high privilege information.