CVE-2016-3159

Severity: low (CVSS 3.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-04-13 · updated 2026-06-17
Weakness: CWE-200

Description

The fpu_fxrstor function in arch/x86/i387.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

Debian Linux: 8.0
Fedoraproject Fedora: 22, 23
Oracle Vm Server: 3.3, 3.4
xen: from 4.3.0 through 4.3.4; from 4.4.0 through 4.4.4; from 4.5.0 through 4.5.3; from 4.6.0 through 4.6.1

References

http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181699.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181729.html
http://support.citrix.com/article/CTX209443
http://www.debian.org/security/2016/dsa-3554
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
http://www.securityfocus.com/bid/85716
http://www.securitytracker.com/id/1035435
http://xenbits.xen.org/xsa/advisory-172.html
http://xenbits.xen.org/xsa/xsa172.patch
http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181699.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181729.html
http://support.citrix.com/article/CTX209443

Get alerted when CVE-2016-3159 or the next vulnerability affects your stack