Vulnerability Description
The xrstor function in arch/x86/xstate.c in Xen 4.x does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allows local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-2076.
CVSS Score
LOW
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | <= 4.4.0 |
| Fedoraproject | Fedora | 22 |
| Oracle | Vm Server | 3.3 |
Related Weaknesses (CWE)
References
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181699.htmlThird Party Advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181729.htmlThird Party Advisory
- http://support.citrix.com/article/CTX209443
- http://www.debian.org/security/2016/dsa-3554
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.htmVendor Advisory
- http://www.securityfocus.com/bid/85714Third Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1035435Third Party AdvisoryVDB Entry
- http://xenbits.xen.org/xsa/advisory-172.htmlVendor Advisory
- http://xenbits.xen.org/xsa/xsa172-4.3.patchPatch
- http://xenbits.xen.org/xsa/xsa172.patchPatch
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181699.htmlThird Party Advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181729.htmlThird Party Advisory
- http://support.citrix.com/article/CTX209443
- http://www.debian.org/security/2016/dsa-3554
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.htmVendor Advisory
FAQ
What is CVE-2016-3158?
CVE-2016-3158 is a vulnerability with a CVSS score of 3.8 (LOW). The xrstor function in arch/x86/xstate.c in Xen 4.x does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allows local guest OS users to obtain sensitive r...
How severe is CVE-2016-3158?
CVE-2016-3158 has been rated LOW with a CVSS base score of 3.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2016-3158?
Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen, Fedoraproject Fedora, Oracle Vm Server.