Xen 4.5.x/4.6.x/4.7.x/4.8.x/4.9.x Transitive Grant Processing access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.00

A vulnerability classified as critical was found in Xen 4.5.x/4.6.x/4.7.x/4.8.x/4.9.x (Virtualization Software). Affected by this vulnerability is some unknown processing of the component Transitive Grant Processing. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Xen allows local OS guest users to cause a denial of service (crash) or possibly obtain sensitive information or gain privileges via vectors involving transitive grants.

The bug was discovered 08/15/2017. The weakness was released 08/15/2017 by Jan Beulich as XSA-226 as confirmed security advisory (Website). It is possible to read the advisory at xenbits.xen.org. This vulnerability is known as CVE-2017-12135 since 08/01/2017. Attacking locally is a requirement. Required for exploitation is a single authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 102526 (Citrix XenServer Multiple Vulnerabilities (CTX225941)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Misc. and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 390007 (Oracle VM Server for x86 Security Update for xen (OVMSA-2017-0142)).

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (102526). Entries connected to this vulnerability are available at 101094, 105309, 105388 and 105389.

Productinfo

Type

Name

Version

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: 7.0
VulDB Meta Temp Score: 6.9

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 102526
Nessus Name: Citrix XenServer Multiple Vulnerabilities (CTX225941)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 53376
OpenVAS Name: Debian Security Advisory DSA 3969-1 (xen - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

08/01/2017 🔍
08/15/2017 +14 days 🔍
08/15/2017 +0 days 🔍
08/15/2017 +0 days 🔍
08/15/2017 +0 days 🔍
08/16/2017 +1 days 🔍
08/16/2017 +0 days 🔍
08/16/2017 +0 days 🔍
08/24/2017 +8 days 🔍
11/07/2019 +805 days 🔍

Sourcesinfo

Advisory: XSA-226
Researcher: Jan Beulich
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-12135 (🔍)
OVAL: 🔍

SecurityTracker: 1039178
SecurityFocus: 100344 - Xen CVE-2017-12135 Multiple Denial of Service Vulnerabilities

See also: 🔍

Entryinfo

Created: 08/16/2017 22:17
Updated: 11/07/2019 15:46
Changes: 08/16/2017 22:17 (80), 11/07/2019 15:46 (5)
Complete: 🔍

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