XenSource Xen 4.5.3/4.6.3/4.7.0 on x64 Instruction Pointer access control

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.8$0-$5k0.00

A vulnerability classified as critical was found in XenSource Xen 4.5.3/4.6.3/4.7.0 on x64 (Virtualization Software). Affected by this vulnerability is some unknown functionality of the component Instruction Pointer. 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 4.5.3, 4.6.3, and 4.7.x allow local HVM guest OS administrators to overwrite hypervisor memory and consequently gain host OS privileges by leveraging mishandling of instruction pointer truncation during emulation.

The weakness was disclosed 09/08/2016 by Brian Marcotte as XSA-186 as confirmed security advisory (Website). It is possible to read the advisory at xenbits.xen.org. The public release has been coordinated in cooperation with XenSource. This vulnerability is known as CVE-2016-7093 since 08/25/2016. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of 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 94780 (Fedora 25 : xen (2016-1d8429b89f)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276119 (Fedora Security Update for xen (FEDORA-2016-1d8429b89f)).

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 (94780). The entries 91386, 91388 and 91389 are pretty similar.

Productinfo

Type

Vendor

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: 8.2
VulDB Meta Temp Score: 8.0

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.2
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

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

NVD Base Score: 🔍

Exploitinginfo

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

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

Nessus ID: 94780
Nessus Name: Fedora 25 : xen (2016-1d8429b89f)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 900325
OpenVAS Name: Fedora Update for xen FEDORA-2016-7d2c67d1f5
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

08/25/2016 🔍
09/08/2016 +14 days 🔍
09/08/2016 +0 days 🔍
09/08/2016 +0 days 🔍
09/09/2016 +1 days 🔍
09/09/2016 +0 days 🔍
09/21/2016 +12 days 🔍
11/15/2016 +55 days 🔍
04/15/2019 +881 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: XSA-186
Researcher: Brian Marcotte
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2016-7093 (🔍)
SecurityTracker: 1036752
SecurityFocus: 92865 - Xen CVE-2016-7093 Local Privilege Escalation Vulnerability

See also: 🔍

Entryinfo

Created: 09/09/2016 10:36
Updated: 04/15/2019 16:13
Changes: 09/09/2016 10:36 (75), 04/15/2019 16:13 (12)
Complete: 🔍
Cache ID: 18:6FF:103

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Might our Artificial Intelligence support you?

Check our Alexa App!