CVE-2016-3159 Information

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.

CVSS Vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

Reference

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

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

CHANGED

Integrity Impact

LOW

Availability Impact

NONE

Base Score

NONE

Base Severity

3.8