Xen up to 4.6.x on 64-bit Failsafe Callback 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, was found in Xen up to 4.6.x on 64-bit. The affected element is an unknown function of the component Failsafe Callback Handler. Such manipulation leads to access control. This vulnerability is documented as CVE-2017-8905. The attack needs to be performed locally. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Xen up to 4.6.x on 64-bit (Virtualization Software). It has been rated as critical. Affected by this issue is some unknown functionality of the component Failsafe Callback Handler. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-264. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Xen through 4.6.x on 64-bit platforms mishandles a failsafe callback, which might allow PV guest OS users to execute arbitrary code on the host OS, aka XSA-215.

The bug was discovered 05/02/2017. The weakness was released 05/11/2017 by Jann Horn with Google Project Zero (Website). The advisory is shared for download at blog.xenproject.org. This vulnerability is handled as CVE-2017-8905 since 05/11/2017. The exploitation is known to be easy. The attack needs to be approached locally. A simple authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1068.

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 100198 (Fedora 24 : xen (2017-c9d71f0860)), 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 3 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (100198) and SecurityFocus (BID 98436†). Entries connected to this vulnerability are available at VDB-101094 and VDB-101095. VulDB is the best source for vulnerability data and more expert information about this specific topic.

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: 100198
Nessus Name: Fedora 24 : xen (2017-c9d71f0860)
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 🔍
05/14/2017 +2 days 🔍
05/16/2017 +2 days 🔍
12/06/2022 +2030 days 🔍

Sourcesinfo

Advisory: FEDORA-2017-c9d71f0860
Researcher: Jann Horn
Organization: Google Project Zero
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-8905 (🔍)
GCVE (CVE): GCVE-0-2017-8905
GCVE (VulDB): GCVE-100-101096
SecurityFocus: 98436 - Xen CVE-2017-8905 Arbitrary Code Execution Vulnerability
OSVDB: - CVE-2017-8905 - Xen - Code Execution Issue
SecurityTracker: 1038388

See also: 🔍

Entryinfo

Created: 05/12/2017 14:39
Updated: 12/06/2022 11:04
Changes: 05/12/2017 14:39 (75), 09/25/2020 14:26 (9), 12/23/2020 10:10 (2), 12/06/2022 11:04 (3)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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