Synopsis
The remote SuSE 11 host is missing one or more security updates.
Description
Three security issues were found in XEN.
Two security issues are fixed by this update :
- Due to incorrect fault handling in the XEN hypervisor it was possible for a XEN guest domain administrator to execute code in the XEN host environment.
(CVE-2012-0217)
- Also a guest user could crash the guest XEN kernel due to a protection fault bounce. The third fix is changing the Xen behaviour on certain hardware:. (CVE-2012-0218)
- The issue is a denial of service issue on older pre-SVM AMD CPUs (AMD Erratum 121). AMD Erratum #121 is described in 'Revision Guide for AMD Athlon 64 and AMD Opteron Processors':
http://support.amd.com/us/Processor_TechDocs/25759.pdf.
(CVE-2012-2934)
The following 130nm and 90nm (DDR1-only) AMD processors are subject to this erratum :
- First-generation AMD-Opteron(tm) single and dual core processors in either 939 or 940 packages :
- AMD Opteron(tm) 100-Series Processors
- AMD Opteron(tm) 200-Series Processors
- AMD Opteron(tm) 800-Series Processors
- AMD Athlon(tm) processors in either 754, 939 or 940 packages
- AMD Sempron(tm) processor in either 754 or 939 packages
- AMD Turion(tm) Mobile Technology in 754 package This issue does not effect Intel processors.
The impact of this flaw is that a malicious PV guest user can halt the host system.
As this is a hardware flaw, it is not fixable except by upgrading your hardware to a newer revision, or not allowing untrusted 64bit guestsystems.
The patch changes the behaviour of the host system booting, which makes it unable to create guest machines until a specific boot option is set.
There is a new XEN boot option 'allow_unsafe' for GRUB which allows the host to start guests again.
This is added to /boot/grub/menu.lst in the line looking like this :
kernel /boot/xen.gz .... allow_unsafe
Note: .... in this example represents the existing boot options for the host.
Solution
Apply SAT patch number 6399.
Plugin Details
File Name: suse_11_xen-201206-120606.nasl
Agent: unix
Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Vulnerability Information
CPE: p-cpe:/a:novell:suse_linux:11:xen, p-cpe:/a:novell:suse_linux:11:xen-tools-domu, p-cpe:/a:novell:suse_linux:11:xen-libs, p-cpe:/a:novell:suse_linux:11:xen-tools, cpe:/o:novell:suse_linux:11, p-cpe:/a:novell:suse_linux:11:xen-doc-html, p-cpe:/a:novell:suse_linux:11:xen-doc-pdf, p-cpe:/a:novell:suse_linux:11:xen-kmp-pae, p-cpe:/a:novell:suse_linux:11:xen-kmp-trace, p-cpe:/a:novell:suse_linux:11:xen-kmp-default
Required KB Items: Host/local_checks_enabled, Host/cpu, Host/SuSE/release, Host/SuSE/rpm-list
Exploit Ease: Exploits are available
Patch Publication Date: 6/6/2012
Exploitable With
CANVAS (CANVAS)
Core Impact
Metasploit (FreeBSD Intel SYSRET Privilege Escalation)