CVE-2016-9379

Publication date 23 January 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The pygrub boot loader emulator in Xen, when S-expression output format is requested, allows local pygrub-using guest OS administrators to read or delete arbitrary files on the host via string quotes and S-expressions in the bootloader configuration file.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
xen	17.04 zesty	Fixed 4.8.0-1ubuntu1
	16.10 yakkety	Fixed 4.7.0-0ubuntu2.1
	16.04 LTS xenial	Fixed 4.6.0-1ubuntu4.3
	14.04 LTS trusty	Fixed 4.4.2-0ubuntu0.14.04.9
	12.04 LTS precise	Fixed 4.1.6.1-0ubuntu0.12.04.13

Notes

mdeslaur

This is XSA-198

tyhicks

issue present in xen-utils-4.x binary packages which are in universe

Severity score breakdown

Parameter	Value
Base score	7.9 · High
Attack vector	Local
Attack complexity	Low
Privileges required	High
User interaction	None
Scope	Changed
Confidentiality	High
Integrity impact	High
Availability impact	None
Vector	CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N