QEMU hw/display/vmware_vga.c vmsvga_fifo_run cursor.mask[]/cursor.image[] out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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4.3$0-$5k0.00

A vulnerability, which was classified as problematic, has been found in QEMU (Virtualization Software) (the affected version is unknown). This issue affects the function vmsvga_fifo_run of the file hw/display/vmware_vga.c. The manipulation of the argument cursor.mask[]/cursor.image[] with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is availability. The summary by CVE is:

The vmsvga_fifo_run function in hw/display/vmware_vga.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via vectors related to cursor.mask[] and cursor.image[] array sizes when processing a DEFINE_CURSOR svga command.

The bug was discovered 12/09/2016. The weakness was disclosed 12/10/2016 by Qinghao Tang (Website). It is possible to read the advisory at git.qemu.org. The identification of this vulnerability is CVE-2016-7170 since 09/08/2016. Attacking locally is a requirement. A simple authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 93970 (Debian DLA-653-1 : qemu-kvm security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276208 (Fedora Security Update for qemu (FEDORA-2016-a56fb613a8)).

Upgrading eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (93970). The entries 92450, 92454, 93307 and 93994 are pretty similar.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.3

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.4
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 93970
Nessus Name: Debian DLA-653-1 : qemu-kvm security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 65001
OpenVAS Name: Fedora Update for qemu FEDORA-2016-3d3218ec41
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Patch: 167d97a3def77ee2dbf6e908b0ecbfe2103977db

Timelineinfo

09/08/2016 🔍
09/12/2016 +4 days 🔍
10/11/2016 +29 days 🔍
10/12/2016 +1 days 🔍
12/09/2016 +58 days 🔍
12/09/2016 +0 days 🔍
12/10/2016 +1 days 🔍
12/10/2016 +0 days 🔍
10/05/2022 +2125 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: DLA 1599-1
Researcher: Qinghao Tang
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-7170 (🔍)
SecurityFocus: 92904 - QEMU CVE-2016-7170 Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 12/10/2016 13:38
Updated: 10/05/2022 10:53
Changes: 12/10/2016 13:38 (63), 06/22/2019 18:40 (16), 10/05/2022 10:53 (6)
Complete: 🔍

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