QEMU Cirrus CLGD 54xx VGA Emulator divide by zero

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability was found in QEMU. It has been rated as problematic. This impacts an unknown function of the component Cirrus CLGD 54xx VGA Emulator. This manipulation causes divide by zero. This vulnerability is registered as CVE-2016-9921. The attack needs to be launched locally. No exploit is available.

Detailsinfo

A vulnerability has been found in QEMU (Virtualization Software) (version unknown) and classified as problematic. Affected by this vulnerability is an unknown function of the component Cirrus CLGD 54xx VGA Emulator. The manipulation with an unknown input leads to a divide by zero vulnerability. The CWE definition for the vulnerability is CWE-369. The product divides a value by zero. As an impact it is known to affect availability. The summary by CVE is:

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.

The bug was discovered 12/23/2016. The weakness was published 12/23/2016 by Qinghao Tang with Qihoo 360 (oss-sec). It is possible to read the advisory at openwall.com. This vulnerability is known as CVE-2016-9921 since 12/08/2016. Attacking locally is a requirement. The successful exploitation requires a single authentication. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 900039 , which helps to determine the existence of the flaw in a target environment. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276405 (Fedora Security Update for qemu (FEDORA-2017-b953d4d3a4)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (900039) and SecurityFocus (BID 94803†). Similar entries are available at VDB-94722, VDB-94723, VDB-94726 and VDB-97328. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.9

VulDB Base Score: 3.3
VulDB Temp Score: 3.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Divide by zero
CWE: CWE-369 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 900039
Nessus File: 🔍

OpenVAS ID: 865785
OpenVAS Name: Fedora Update for xen FEDORA-2016-1b868c23a9
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/08/2016 🔍
12/08/2016 +0 days 🔍
12/23/2016 +15 days 🔍
12/23/2016 +0 days 🔍
12/23/2016 +0 days 🔍
12/24/2016 +1 days 🔍
10/12/2022 +2118 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: RHSA-2017:2392
Researcher: Qinghao Tang
Organization: Qihoo 360
Status: Not defined

CVE: CVE-2016-9921 (🔍)
GCVE (CVE): GCVE-0-2016-9921
GCVE (VulDB): GCVE-100-94675
SecurityFocus: 94803 - QEMU Divide By Zero Multiple Denial of Service Vulnerabilities

See also: 🔍

Entryinfo

Created: 12/24/2016 18:28
Updated: 10/12/2022 16:58
Changes: 12/24/2016 18:28 (64), 07/24/2019 16:18 (6), 10/12/2022 16:58 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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