CVE-2016-9383: Citrix Xenserver

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Xen, when running on a 64-bit hypervisor, allows local x86 guest OS users to modify arbitrary memory and consequently obtain sensitive information, cause a denial of service (host crash), or execute arbitrary code on the host by leveraging broken emulation of bit test instructions.

Affected products

• Citrix Xenserver: version 6.0.2 only; version 6.2.0 only; version 6.5 only; version 7.0 only
• Xen Xen: any version

Published 2017-01-23. Last modified 2026-06-17.