Debian Security Advisory

DLA-571-1 xen -- LTS security update

Date Reported:
30 Jul 2016
Affected Packages:
xen
Vulnerable:
Yes
Security database references:
In Mitre's CVE dictionary: CVE-2014-3672, CVE-2016-3158, CVE-2016-3159, CVE-2016-3710, CVE-2016-3712, CVE-2016-3960, CVE-2016-4480, CVE-2016-6258.
More information:

Multiple vulnerabilities have been discovered in the Xen hypervisor. The Common Vulnerabilities and Exposures project identifies the following problems:

  • CVE-2014-3672 (XSA-180)

    Andrew Sorensen discovered that a HVM domain can exhaust the hosts disk space by filling up the log file.

  • CVE-2016-3158 / CVE-2016-3159 (XSA-172)

    Jan Beulich from SUSE discovered that Xen does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors. A malicious domain can take advantage of this flaw to obtain address space usage and timing information, about another domain, at a fairly low rate.

  • CVE-2016-3710 (XSA-179)

    Wei Xiao and Qinghao Tang of 360.cn Inc discovered an out-of-bounds read and write flaw in the QEMU VGA module. A privileged guest user could use this flaw to execute arbitrary code on the host with the privileges of the hosting QEMU process.

  • CVE-2016-3712 (XSA-179)

    Zuozhi Fzz of Alibaba Inc discovered potential integer overflow or out-of-bounds read access issues in the QEMU VGA module. A privileged guest user could use this flaw to mount a denial of service (QEMU process crash).

  • CVE-2016-3960 (XSA-173)

    Ling Liu and Yihan Lian of the Cloud Security Team, Qihoo 360 discovered an integer overflow in the x86 shadow pagetable code. A HVM guest using shadow pagetables can cause the host to crash. A PV guest using shadow pagetables (i.e. being migrated) with PV superpages enabled (which is not the default) can crash the host, or corrupt hypervisor memory, potentially leading to privilege escalation.

  • CVE-2016-4480 (XSA-176)

    Jan Beulich discovered that incorrect page table handling could result in privilege escalation inside a Xen guest instance.

  • CVE-2016-6258 (XSA-182)

    Jérémie Boutoille discovered that incorrect pagetable handling in PV instances could result in guest to host privilege escalation.

  • Additionally this Xen Security Advisory without a CVE was fixed: XSA-166

    Konrad Rzeszutek Wilk and Jan Beulich discovered that ioreq handling is possibly susceptible to a multiple read issue.

For Debian 7 Wheezy, these problems have been fixed in version 4.1.6.lts1-1.

We recommend that you upgrade your xen packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS