CVE-2016-7777

Publication date 7 October 2016

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

Xen 4.7.x and earlier does not properly honor CR0.TS and CR0.EM, which allows local x86 HVM guest OS users to read or modify FPU, MMX, or XMM register state information belonging to arbitrary tasks on the guest by modifying an instruction while the hypervisor is preparing to emulate it.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
xen	16.04 LTS xenial	Fixed 4.6.0-1ubuntu4.2
	14.04 LTS trusty	Fixed 4.4.2-0ubuntu0.14.04.7
	12.04 LTS precise	Fixed 4.1.6.1-0ubuntu0.12.04.12

Notes

sbeattie

The vulnerability is only exposed to x86 HVM guests.

Severity score breakdown

Parameter	Value
Base score	6.3 · Medium
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	None
Vector	CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N