Xen up to 4.8.x Hypervisor input validation

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Xen up to 4.8.x. Affected by this vulnerability is an unknown functionality of the component Hypervisor. Executing a manipulation can lead to input validation. This vulnerability appears as CVE-2017-10923. The attack may be performed from remote. There is no available exploit. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability was found in Xen up to 4.8.x (Virtualization Software). It has been declared as problematic. This vulnerability affects an unknown functionality of the component Hypervisor. 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 availability. CVE summarizes:

Xen through 4.8.x does not validate a vCPU array index upon the sending of an SGI, which allows guest OS users to cause a denial of service (hypervisor crash), aka XSA-225.

The bug was discovered 06/20/2017. The weakness was presented 07/05/2017 as XSA-225 as confirmed security advisory (Website). The advisory is shared for download at xenbits.xen.org. This vulnerability was named CVE-2017-10923 since 07/04/2017. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 14 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 101638 (Fedora 26 : xen (2017-5c6a9b07a3)), 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 276751 (Fedora Security Update for xen (FEDORA-2017-c3149b5fcb)).

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 (101638) and SecurityFocus (BID 99160†). See VDB-103037, VDB-103038, VDB-103039 and VDB-103040 for similar entries. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 101638
Nessus Name: Fedora 26 : xen (2017-5c6a9b07a3)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for xen FEDORA-2017-c3149b5fcb
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

06/20/2017 🔍
06/20/2017 +0 days 🔍
07/04/2017 +14 days 🔍
07/04/2017 +0 days 🔍
07/05/2017 +1 days 🔍
07/05/2017 +0 days 🔍
07/05/2017 +0 days 🔍
07/17/2017 +12 days 🔍
12/30/2020 +1262 days 🔍

Sourcesinfo

Advisory: XSA-225
Researcher: Julien Grall
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-10923 (🔍)
GCVE (CVE): GCVE-0-2017-10923
GCVE (VulDB): GCVE-100-103048
SecurityFocus: 99160 - Xen 'xen/arch/arm/vgic.c' Denial of Service Vulnerability
SecurityTracker: 1038735

See also: 🔍

Entryinfo

Created: 07/05/2017 10:32
Updated: 12/30/2020 17:57
Changes: 07/05/2017 10:32 (76), 10/22/2019 10:41 (4), 12/30/2020 17:51 (3), 12/30/2020 17:57 (1)
Complete: 🔍
Cache ID: 216::103

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