CVE-2015-8555: Infoleak

Published Apr 13, 2016

Updated

Xen 4.6.x, 4.5.x, 4.4.x, 4.3.x, and earlier do not initialize x86 FPU stack and XMM registers when XSAVE/XRSTOR are not used to manage guest extended register state, which allows local guest domains to obtain sensitive information from other domains via unspecified vectors.

Affected Software

17 affected components

Citrix XenServer=6.0

XEN Xen=4.3.0

XEN Xen=4.3.1

XEN Xen=4.3.2

XEN Xen=4.3.3

XEN Xen=4.3.4

XEN Xen=4.4.0

XEN Xen=4.4.1

XEN Xen=4.4.2

XEN Xen=4.4.3

XEN Xen=4.4.4

XEN Xen=4.5.0

XEN Xen=4.5.1

XEN Xen=4.5.2

XEN Xen=4.5.3

XEN Xen=4.6.0

XEN Xen=4.6.1

Remediation

Patch Available

http://xenbits.xen.org/xsa/advisory-165.html

Event History

Apr 13, 2016

CVE Published

via MITRE·03:00 PM

Data Sourced

via MITRE·03:00 PM

Description

Frequently Asked Questions

What is the severity of CVE-2015-8555?

CVE-2015-8555 has a medium severity rating that indicates potential risks of information disclosure.

How do I fix CVE-2015-8555?

To fix CVE-2015-8555, the affected version of Xen should be updated to a patched release that properly initializes the FPU stack and XMM registers.

Who is affected by CVE-2015-8555?

CVE-2015-8555 affects installations of Xen 4.3.x through 4.6.x, including various XenServer versions.

What does CVE-2015-8555 exploit?

CVE-2015-8555 exploits improper initialization of the FPU stack and XMM registers, allowing local guest domains to access sensitive information from other guest domains.

Is CVE-2015-8555 still a concern?

While CVE-2015-8555 has been addressed in later versions, systems running outdated versions of Xen remain at risk.