A guest administrator who is granted access to the graphical console
of a Xen guest can access the qemu monitor. The monitor can be used
to access host resources.
A malicious guest administrator can access host resources (perhaps
belonging to other guests or the underlying system) and may be able to
escalate their privilege to that of the host.
References:
http://seclists.org/oss-sec/2012/q3/390
Acknowledgements:
Red Hat would like to thank the Xen project for reporting this issue.
Statement:
Not vulnerable.
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 as we did not have support for Xen hypervisor.