CVE-2016-9923

Publication date 23 December 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Quick Emulator (Qemu) built with the 'chardev' backend support is vulnerable to a use after free issue. It could occur while hotplug and unplugging the device in the guest. A guest user/process could use this flaw to crash a Qemu process on the host resulting in DoS.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
qemu	17.10 artful	Not affected
	17.04 zesty	Not affected
	16.10 yakkety	Ignored end of life
	16.04 LTS xenial	Ignored
	14.04 LTS trusty	Ignored
	12.04 LTS precise	Not in release
qemu-kvm	17.10 artful	Not in release
	17.04 zesty	Not in release
	16.10 yakkety	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
	12.04 LTS precise	Ignored end of life

Notes

mdeslaur

complex backport, we're not going to dix this in xenial and older

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
qemu	Upstream: http://git.qemu-project.org/?p=qemu.git;a=commit;h=a4afa548fc6dd9842ed86639b4d37d4d1c4ad480

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.5 · Medium

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	5.5 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H