The MITRE CVE dictionary describes this issue as:
The ioapic_read_indirect function in virt/kvm/ioapic.c in the Linux kernel through 3.8.4 does not properly handle a certain combination of invalid IOAPIC_REG_SELECT and IOAPIC_REG_WINDOW operations, which allows guest OS users to obtain sensitive information from host OS memory or cause a denial of service (host OS OOPS) via a crafted application.
Find out more about CVE-2013-1798 from the
MITRE CVE dictionary dictionary and
This issue did not affect the versions of Linux kernel as shipped with Red Hat
Enterprise Linux 5 and Red Hat Enterprise MRG as they did not provide support
for the KVM subsystem.