http://support.citrix.com/article/CTX142593
Windows用のXenToolsのアップデート。
ブルースクリーンの時のCrash-Dump用ドライバの修正(そんなのがあるんだね)とか、
前のXenToolsがキレイにUninstallできない問題の修正(まだダメなのね)とか。
XenServer 6.2 (clearwater) と XenServer 6.5 (Creedence) を中心に雑な感じで書いていきます。といいながら、すでにXenServer8がリリースされている・・・
CVE-2015-4106 (Medium): Unmediated PCI register access in qemu.
CVE-2015-4163 (Medium): GNTTABOP_swap_grant_ref operation misbehavior.
CVE-2015-4164 (Medium): vulnerability in the iret hypercall handler
CVE-2015-2756 (Low): Unmediated PCI command register access in qemu
CVE-2015-4103 (Low): Potential unintended writes to host MSI message data field via qemu.
CVE-2015-4104 (Low): PCI MSI mask bits inadvertently exposed to guests.
CVE-2015-4105 (Low): Guest triggerable qemu MSI-X pass-through error messages
ISSUE DESCRIPTION
=================
The code in qemu which emulates a floppy disk controller did not
correctly bounds check accesses to an array and therefore was
vulnerable to a buffer overflow attack.
Description of Problem
Citrix is aware of the recent vulnerability that has been reported against the Xen hypervisor. This issue is known as the 'VENOM' vulnerability and has been assigned the following CVE number:
CVE-2015-3456: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-3456
The following sections will provide guidance to customers on the potential impact of this issue. Citrix is actively analysing the impact of this vulnerability on supported versions of Citrix XenServer. Additional details and guidance will be added to this document as soon as they are available.
We believe that code execution is possible but we have not yet seen any working reproducers that would allow this.なお、既存のExploitは、QEMUをCrashさせるので、Segfault LOGをみてれば、その攻撃を判定できそうとのこと。