CVE-2016-9921

Qemu: display: cirrus_vga: a divide by zero in cirrus_do_copy

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

Quick emulator (Qemu) built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to a divide by zero issue. It could occur while copying VGA data when cirrus graphics mode was set to be VGA. A privileged user inside guest could use this flaw to crash the Qemu process instance on the host, resulting in DoS.

Quick emulator (Qemu) construido con el soporte Cirrus CLGD 54xx VGA Emulator es vulnerable a un problema de división por cero. Podría ocurrir mientras se copian datos VGA cuando el modo de gráficos cirrus estaba configurado para ser VGA. Un usuario privilegiado dentro del huésped podría usar esta falla para bloquear la instancia del proceso Qemu en el host, resultando en DoS.

*Credits: N/A

CVSS Scores

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Adjacent

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

None

Availability

Low

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

Attack Vector

Adjacent

Attack Complexity

Medium

Authentication

Single

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2016-12-08 CVE Reserved
2016-12-23 CVE Published
2023-03-08 EPSS Updated
2024-08-06 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-369: Divide By Zero

CAPEC

References (8)

URL	Tag	Source
http://www.securityfocus.com/bid/94803	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/09/msg00007.html	Mailing List

URL	Date	SRC

URL	Date	SRC
http://www.openwall.com/lists/oss-security/2016/12/09/1	2023-02-13

URL	Date	SRC
https://access.redhat.com/errata/RHSA-2017:2392	2023-02-13
https://access.redhat.com/errata/RHSA-2017:2408	2023-02-13
https://security.gentoo.org/glsa/201701-49	2023-02-13
https://access.redhat.com/security/cve/CVE-2016-9921	2017-08-01
https://bugzilla.redhat.com/show_bug.cgi?id=1334398	2017-08-01

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Redhat Search vendor "Redhat"	Virtualization Search vendor "Redhat" for product "Virtualization"	4.0 Search vendor "Redhat" for product "Virtualization" and version "4.0"	-	Affected	in	Redhat Search vendor "Redhat"	Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"	7.0 Search vendor "Redhat" for product "Enterprise Linux" and version "7.0"	-	Safe
Qemu Search vendor "Qemu"		Qemu Search vendor "Qemu" for product "Qemu"				<= 2.7.1 Search vendor "Qemu" for product "Qemu" and version " <= 2.7.1"		-		Affected
Qemu Search vendor "Qemu"		Qemu Search vendor "Qemu" for product "Qemu"				2.8.0 Search vendor "Qemu" for product "Qemu" and version "2.8.0"		rc0		Affected
Qemu Search vendor "Qemu"		Qemu Search vendor "Qemu" for product "Qemu"				2.8.0 Search vendor "Qemu" for product "Qemu" and version "2.8.0"		rc1		Affected
Qemu Search vendor "Qemu"		Qemu Search vendor "Qemu" for product "Qemu"				2.8.0 Search vendor "Qemu" for product "Qemu" and version "2.8.0"		rc2		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				8.0 Search vendor "Debian" for product "Debian Linux" and version "8.0"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				6.0 Search vendor "Redhat" for product "Openstack" and version "6.0"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				7.0 Search vendor "Redhat" for product "Openstack" and version "7.0"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				8 Search vendor "Redhat" for product "Openstack" and version "8"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				9 Search vendor "Redhat" for product "Openstack" and version "9"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				10 Search vendor "Redhat" for product "Openstack" and version "10"		-		Affected
Redhat Search vendor "Redhat"		Openstack Search vendor "Redhat" for product "Openstack"				11 Search vendor "Redhat" for product "Openstack" and version "11"		-		Affected