CVE-2016-3158
Publication date 13 April 2016
Last updated 25 August 2025
Ubuntu priority
Description
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| xen | 16.04 LTS xenial |
Fixed 4.6.0-1ubuntu4.1
|
| 14.04 LTS trusty |
Fixed 4.4.2-0ubuntu0.14.04.6
|
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
3.8 · Low
|
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Changed |
| Confidentiality | Low |
| Integrity impact | None |
| Availability impact | None |
| Vector | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N |