Xen Hypervisor New CPU Interrupt Descriptor Table (IDT) Copy Handling Guest-to-Host Privilege Escalation (XSA-244)
Medium Nessus Plugin ID 103979
SynopsisThe remote Xen hypervisor installation is missing a security update.
DescriptionAccording to its self-reported version number, the Xen hypervisor installed on the remote host is affected by an unspecified flaw that is triggered when, as a new CPU is brought online, it copies certain selector fields from CPU0's Interrupt Descriptor Table (IDT) while CPU0 is in HVM context. This may result in incorrect values being copied, allowing an attacker on the guest to cause a denial of service or gain elevated privileges on the host.
Note that Nessus has checked the changeset versions based on the xen.git change log. Nessus did not check guest hardware configurations or if patches were applied manually to the source code before a recompile and reinstall.
SolutionApply the appropriate patch according to the vendor advisory.