Buffer overflow in the complete_emulated_mmio function in arch/x86/kvm/x86.c in the Linux kernel before 3.13.6 allows guest OS users to execute arbitrary code on the host OS by leveraging a loop that triggers an invalid memory copy affecting certain cancel_work_item data.
Buffer Copy without Checking Size of Input The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.