The VGA emulator in QEMU allows local guest users to read host memory by setting the display to a high resolution.
http://git.qemu.org/?p=qemu.git;a=commit;h=ab9509cceabef28071e41bdfa073083859c949a7
http://git.qemu.org/?p=qemu.git;a=commitdiff;h=c1b886c45dc70f247300f549dce9833f3fa2def5
http://lists.opensuse.org/opensuse-security-announce/2015-04/msg00014.html
http://rhn.redhat.com/errata/RHSA-2014-1669.html
http://rhn.redhat.com/errata/RHSA-2014-1670.html
http://rhn.redhat.com/errata/RHSA-2014-1941.html
http://secunia.com/advisories/61829
http://support.citrix.com/article/CTX200892
http://www.debian.org/security/2014/dsa-3044
http://www.securityfocus.com/bid/69654