Xen 4.6.x/4.7.x/4.8.x/4.9.x Grant Table Allocator race condition

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.
6.3$0-$5k0.00

A vulnerability was found in Xen 4.6.x/4.7.x/4.8.x/4.9.x (Virtualization Software). It has been rated as critical. This issue affects an unknown code of the component Grant Table Allocator. The manipulation with an unknown input leads to a race condition vulnerability. Using CWE to declare the problem leads to CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Race condition in the grant table code in Xen 4.6.x through 4.9.x allows local guest OS administrators to cause a denial of service (free list corruption and host crash) or gain privileges on the host via vectors involving maptrack free list handling.

The bug was discovered 08/15/2017. The weakness was shared 08/15/2017 by Ian Jackson with Citrix as XSA-228 as confirmed security advisory (Website). The advisory is shared at xenbits.xen.org. The identification of this vulnerability is CVE-2017-12136 since 08/01/2017. An attack has to be approached locally. A simple authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

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 176145 (Debian Security Update for xen (DSA 3969-1)).

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). The entries 105309, 105388 and 105391 are related to this item.

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: 6.5
VulDB Meta Temp Score: 6.4

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

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

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

NVD Base Score: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

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-228
Researcher: Ian Jackson
Organization: Citrix
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-12136 (🔍)
OVAL: 🔍

SecurityTracker: 1039175
SecurityFocus: 100346 - Xen CVE-2017-12136 Privilege Escalation Vulnerability

See also: 🔍

Entryinfo

Created: 08/16/2017 22:14
Updated: 11/07/2019 15:39
Changes: 08/16/2017 22:14 (81), 11/07/2019 15:39 (5)
Complete: 🔍

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Are you interested in using VulDB?

Download the whitepaper to learn more about our service!