XenSource Xen 4.3/4.4/4.5/4.6 x86 Shadow Pagetable null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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8.3$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in XenSource Xen 4.3/4.4/4.5/4.6. This affects an unknown part of the component x86 Shadow Pagetable Handler. Performing a manipulation results in null pointer dereference. This vulnerability is reported as CVE-2016-3960. The attack is possible to be carried out remotely. No exploit exists. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability classified as critical has been found in XenSource Xen 4.3/4.4/4.5/4.6 (Virtualization Software). This affects some unknown processing of the component x86 Shadow Pagetable Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Integer overflow in the x86 shadow pagetable code in Xen allows local guest OS users to cause a denial of service (host crash) or possibly gain privileges by shadowing a superpage mapping.

The weakness was disclosed 04/18/2016 by Security Team with Qihoo 360 as XSA-173 as confirmed security advisory (Website). The advisory is shared at xenbits.xen.org. This vulnerability is uniquely identified as CVE-2016-3960 since 04/05/2016. The exploitability is told to be easy. An attack has to be approached locally. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 93296 (SUSE SLED12 / SLES12 Security Update : xen (SUSE-SU-2016:2093-1) (Bunker Buster)), 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. The commercial vulnerability scanner Qualys is able to test this issue with plugin 169079 (SUSE Enterprise Linux Security Update for xen (SUSE-SU-2016:2100-1)).

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 databases at X-Force (112325), Tenable (93296) and SecurityFocus (BID 86318†). The entries VDB-81555, VDB-81556 and VDB-87721 are pretty similar. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.9
VulDB Meta Temp Score: 8.3

VulDB Base Score: 9.0
VulDB Temp Score: 7.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 93296
Nessus Name: SUSE SLED12 / SLES12 Security Update : xen (SUSE-SU-2016:2093-1) (Bunker Buster)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for xen FEDORA-2016-75063477
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
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Timelineinfo

04/05/2016 🔍
04/18/2016 +12 days 🔍
04/18/2016 +0 days 🔍
04/18/2016 +0 days 🔍
04/19/2016 +0 days 🔍
04/19/2016 +0 days 🔍
09/02/2016 +135 days 🔍
07/25/2022 +2152 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: XSA-173
Researcher: Security Team
Organization: Qihoo 360
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-3960 (🔍)
GCVE (CVE): GCVE-0-2016-3960
GCVE (VulDB): GCVE-100-82557

OVAL: 🔍

X-Force: 112325 - Xen x86 shadow pagetable denial of service
SecurityFocus: 86318 - Xen CVE-2016-3960 NULL pointer Dereference Remote Denial of Service Vulnerability
SecurityTracker: 1035587

See also: 🔍

Entryinfo

Created: 04/19/2016 14:23
Updated: 07/25/2022 10:29
Changes: 04/19/2016 14:23 (59), 10/18/2018 08:28 (26), 07/25/2022 10:29 (3)
Complete: 🔍
Cache ID: 216::103

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