CVE-2016-3158: Fedoraproject Fedora

Low severity, CVSS 3.8. EPSS: 0.4% chance of exploitation in the next 30 days.

The xrstor function in arch/x86/xstate.c in Xen 4.x does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allows local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-2076.

Affected products

• Fedoraproject Fedora: version 22 only; version 23 only
• Oracle Vm Server: version 3.3 only; version 3.4 only
• Xen Xen: up to and including 4.4.0

Published 2016-04-13. Last modified 2026-06-17.