A flaw was found in Linux kernel's KVM virtualization subsystem. The VMX code does not restore the GDT.LIMIT to the previous host value, but instead sets it to 64KB. With a corrupted GDT limit a host's userspace code has an ability to place malicious entries in the GDT, particularly to the per-cpu variables. An attacker can use this to escalate their privileges.
The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.