Xen up to 4.8.x Segment Descriptor access control

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Xen up to 4.8.x. Impacted is an unknown function of the component Segment Descriptor Handler. This manipulation causes access control. This vulnerability is registered as CVE-2017-8904. The attack needs to be launched locally. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Xen up to 4.8.x (Virtualization Software). It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component Segment Descriptor Handler. 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 through 4.8.x mishandles the "contains segment descriptors" property during GNTTABOP_transfer (aka guest transfer) operations, which might allow PV guest OS users to execute arbitrary code on the host OS, aka XSA-214.

The bug was discovered 05/02/2017. The weakness was published 05/11/2017 (Website). It is possible to read the advisory at blog.xenproject.org. This vulnerability is known as CVE-2017-8904 since 05/11/2017. The exploitation appears to be easy. Attacking locally is a requirement. The successful exploitation needs a single 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 was handled as a non-public zero-day exploit for at least 9 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 100189 (Fedora 25 : xen (2017-5ae70ac6a5)), 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 276625 (Fedora Security Update for xen (FEDORA-2017-5ae70ac6a5)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 1 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (100189) and SecurityFocus (BID 98428†). Similar entries are available at VDB-101094 and VDB-101096. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

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

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 100189
Nessus Name: Fedora 25 : xen (2017-5ae70ac6a5)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for xen FEDORA-2017-c9d71f0860
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

05/02/2017 🔍
05/11/2017 +9 days 🔍
05/11/2017 +0 days 🔍
05/11/2017 +0 days 🔍
05/11/2017 +0 days 🔍
05/12/2017 +1 days 🔍
05/12/2017 +0 days 🔍
05/16/2017 +4 days 🔍
12/06/2022 +2030 days 🔍

Sourcesinfo

Advisory: FEDORA-2017-5ae70ac6a5
Researcher: the Xen project
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-8904 (🔍)
GCVE (CVE): GCVE-0-2017-8904
GCVE (VulDB): GCVE-100-101095
SecurityFocus: 98428 - Xen CVE-2017-8904 Arbitrary Code Execution Vulnerability
OSVDB: - CVE-2017-8904 - Xen - Code Execution Issue
SecurityTracker: 1038387

See also: 🔍

Entryinfo

Created: 05/12/2017 14:39
Updated: 12/06/2022 10:57
Changes: 05/12/2017 14:39 (74), 09/25/2020 14:20 (7), 12/23/2020 09:59 (2), 12/23/2020 10:05 (1), 12/06/2022 10:57 (3)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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