Red Hat Security Advisory 2013-0630-01 - The kernel packages contain the Linux kernel, the core of any Linux operating system. A flaw was found in the way the xen_iret() function in the Linux kernel used the DS register. A local, unprivileged user in a 32-bit, para-virtualized Xen hypervisor guest could use this flaw to crash the guest or, potentially, escalate their privileges.
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