Xen up to 4.2 MMIO get_user information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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3.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Xen up to 4.2. The impacted element is the function get_user of the component MMIO Handler. Such manipulation leads to information disclosure. This vulnerability is traded as CVE-2017-7995. An attack has to be approached locally. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Xen up to 4.2 (Virtualization Software). It has been rated as problematic. Affected by this issue is the function get_user of the component MMIO Handler. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. CVE summarizes:

Xen PV guest before Xen 4.3 checked access permissions to MMIO ranges only after accessing them, allowing host PCI device space memory reads, leading to information disclosure. This is an error in the get_user function. NOTE: the upstream Xen Project considers versions before 4.5.x to be EOL.

The bug was discovered 05/02/2017. The weakness was shared 05/03/2017 by Jan Beulich (Website). The advisory is shared for download at lists.opensuse.org. This vulnerability is handled as CVE-2017-7995 since 04/21/2017. The attack needs to be approached locally. A simple authentication is required for exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1592.

The vulnerability scanner Nessus provides a plugin with the ID 99961 (SUSE SLES11 Security Update : xen (SUSE-SU-2017:1146-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l.

Upgrading to version 4.3 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (99961) and SecurityFocus (BID 98314†). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.8
VulDB Meta Temp Score: 3.7

VulDB Base Score: 3.8
VulDB Temp Score: 3.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 3.8
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: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
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: 99961
Nessus Name: SUSE SLES11 Security Update : xen (SUSE-SU-2017:1146-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 52434
OpenVAS Name: Debian LTS Advisory ([SECURITY] [DLA 964-1] xen security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Xen 4.3

Timelineinfo

04/21/2017 🔍
05/02/2017 +11 days 🔍
05/02/2017 +0 days 🔍
05/03/2017 +1 days 🔍
05/03/2017 +0 days 🔍
05/03/2017 +0 days 🔍
05/03/2017 +0 days 🔍
05/04/2017 +1 days 🔍
09/23/2020 +1238 days 🔍

Sourcesinfo

Advisory: lists.opensuse.org
Researcher: Jan Beulich
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-7995 (🔍)
GCVE (CVE): GCVE-0-2017-7995
GCVE (VulDB): GCVE-100-100844
SecurityFocus: 98314 - Xen CVE-2017-7995 Information Disclosure Vulnerability
OSVDB: - CVE-2017-7995 - Xen PV - Information Disclosure Issue

Entryinfo

Created: 05/04/2017 08:34
Updated: 09/23/2020 16:07
Changes: 05/04/2017 08:34 (71), 09/23/2020 16:07 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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