XenSource Xen up to 4.6.x on x86 PV Superpage Hypercall input validation

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

Summaryinfo

A vulnerability labeled as critical has been found in XenSource Xen up to 4.6.x on x86. Affected by this issue is some unknown functionality of the component PV Superpage Hypercall Handler. Executing a manipulation can lead to input validation. This vulnerability is handled as CVE-2016-1570. The attack can be executed remotely. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability has been found in XenSource Xen up to 4.6.x on x86 (Virtualization Software) and classified as critical. This vulnerability affects an unknown part of the component PV Superpage Hypercall Handler. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 01/20/2016 by Qinghao Tang with 360 Marvel Team as XSA-167 as confirmed security advisory (Website). The advisory is shared for download at xenbits.xen.org. This vulnerability was named CVE-2016-1570 since 01/11/2016. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The advisory points out:

The PV superpage functionality lacks certain validity checks on data being passed to the hypervisor by guests. This is the case for the page identifier (MFN) passed to MMUEXT_MARK_SUPER and MMUEXT_UNMARK_SUPER sub-ops of the HYPERVISOR_mmuext_op hypercall as well as for various forms of page table updates.

The vulnerability scanner Nessus provides a plugin with the ID 88170 (OracleVM 3.3 : xen (OVMSA-2016-0007)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family OracleVM Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 175674 (Debian Security Update for xen (DSA 3519-1)).

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 Tenable (88170), SecurityTracker (ID 1034744†) and Vulnerability Center (SBV-56030†). Entries connected to this vulnerability are available at VDB-80357 and VDB-81024. Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.6
VulDB Meta Temp Score: 8.3

VulDB Base Score: 8.6
VulDB Temp Score: 8.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 88170
Nessus Name: OracleVM 3.3 : xen (OVMSA-2016-0007)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for xen FEDORA-2016-2
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

01/11/2016 🔍
01/20/2016 +9 days 🔍
01/20/2016 +0 days 🔍
01/20/2016 +0 days 🔍
01/20/2016 +0 days 🔍
01/21/2016 +1 days 🔍
01/21/2016 +0 days 🔍
01/22/2016 +1 days 🔍
01/26/2016 +4 days 🔍
07/03/2022 +2350 days 🔍

Sourcesinfo

Vendor: citrix.com

Advisory: XSA-167
Researcher: Qinghao Tang
Organization: 360 Marvel Team
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-1570 (🔍)
GCVE (CVE): GCVE-0-2016-1570
GCVE (VulDB): GCVE-100-80356

OVAL: 🔍

SecurityTracker: 1034744
Vulnerability Center: 56030 - Xen Local DoS or Code Execution due to an Issue in PV superpage, Medium

See also: 🔍

Entryinfo

Created: 01/21/2016 11:26
Updated: 07/03/2022 20:19
Changes: 01/21/2016 11:26 (69), 07/02/2018 09:19 (21), 07/03/2022 20:19 (3)
Complete: 🔍
Cache ID: 216:BDD:103

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