Processing of the HVMOP_set_mem_access HVM control operations does not check the size of its input and can tie up a physical CPU for extended periods of time.
A malicious administrator of a domain privileged with regard to an HVM guest can cause Xen to become unresponsive leading to a Denial of Service.
Red Hat would like to thank the Xen project for reporting this issue.
This issue did not affect the versions of the kernel-xen package as shipped with Red Hat Enterprise Linux 5.
This issue did not affect Red Hat Enterprise Linux 6 and Red Hat Enterprise MRG 2 as we did not have support for Xen hypervisor.
Created xen tracking bugs for this issue:
Affects: fedora-all [bug 1080425]