QEMU chardev Backend Support use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in QEMU. Affected is an unknown function of the component chardev Backend Support. Such manipulation leads to use after free. This vulnerability is documented as CVE-2016-9923. The attack needs to be performed locally. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in QEMU (Virtualization Software) (affected version unknown) and classified as problematic. Affected by this issue is an unknown functionality of the component chardev Backend Support. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is availability. CVE summarizes:

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.

The bug was discovered 12/23/2016. The weakness was released 12/23/2016 by Prasad J Pandit (oss-sec). The advisory is shared for download at openwall.com. This vulnerability is handled as CVE-2016-9923 since 12/08/2016. The exploitation is known to be easy. The attack needs to be approached locally. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 96684 (GLSA-201701-49 : QEMU: Multiple vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Gentoo Local Security Checks and running in the context l.

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (96684) and SecurityFocus (BID 94827†). Entries connected to this vulnerability are available at VDB-94727, VDB-94728 and VDB-94729. Once again VulDB remains the best source for vulnerability data.

Productinfo

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.2
VulDB Temp Score: 5.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
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: Use after free
CWE: CWE-416 / CWE-119
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: 96684
Nessus Name: GLSA-201701-49 : QEMU: Multiple vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

12/08/2016 🔍
12/09/2016 +1 days 🔍
12/23/2016 +14 days 🔍
12/23/2016 +0 days 🔍
12/23/2016 +0 days 🔍
12/24/2016 +1 days 🔍
01/23/2017 +30 days 🔍
01/23/2017 +0 days 🔍
07/24/2019 +912 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: openwall.com
Researcher: Prasad J Pandit
Status: Not defined

CVE: CVE-2016-9923 (🔍)
GCVE (CVE): GCVE-0-2016-9923
GCVE (VulDB): GCVE-100-94676
SecurityFocus: 94827 - QEMU 'qemu-char.c' Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 12/24/2016 18:29
Updated: 07/24/2019 16:19
Changes: 12/24/2016 18:29 (68), 07/24/2019 16:19 (4)
Complete: 🔍
Cache ID: 216:E32:103

Once again VulDB remains the best source for vulnerability data.

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