CVE-2016-9382

Description

Xen 4.0.x through 4.7.x mishandle x86 task switches to VM86 mode, which allows local 32-bit x86 HVM guest OS users to gain privileges or cause a denial of service (guest OS crash) by leveraging a guest operating system that uses hardware task switching and allows a new task to start in VM86 mode.

CVSS Metrics

• v3.0•HIGH•Score: 7.8CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
• v2.0•MEDIUM•Score: 4.6AV:L/AC:L/Au:N/C:P/I:P/A:P

EPSS Trends

Current EPSS score: 0.12%• Percentile: 31%

Techniques & Countermeasures

• CWE-264•Permissions, Privileges, and Access Controls

  Weaknesses in this category are related to the management of permissions, privileges, and other security features that are used to perform access control.

Affected Systems

• citrix•xenserver

  6.0.2 | 6.2.0 | 6.5 | 7.0

• xen•xen

  4.0.0 | 4.0.1 | 4.0.2 | 4.0.3 | 4.0.4 | 4.1.0 | 4.1.1 | 4.1.2 | 4.1.3 | 4.1.4 | 4.1.5 | 4.1.6.1 | 4.2.0 | 4.2.1 | 4.2.2 | 4.2.3 | 4.2.4 | 4.2.5 | 4.3.0 | 4.3.1 | 4.3.2 | 4.3.3 | 4.3.4 | 4.4.0 | 4.4.1 | 4.4.2 | 4.4.3 | 4.4.4 | 4.5.0 | 4.5.1 | 4.5.2 | 4.5.3 | 4.5.5 | 4.6.0 | 4.6.1 | 4.6.3 | 4.6.4 | 4.7.0 | 4.7.1

References (5)

• http://www.securityfocus.com/bid/94470
• https://security.gentoo.org/glsa/201612-56
• http://xenbits.xen.org/xsa/advisory-192.html
• http://www.securitytracker.com/id/1037341
• https://support.citrix.com/article/CTX218775