The set_pixel_format function in ui/vnc.c in QEMU allows remote attackers to cause a denial of service (crash) via a small bytes_per_pixel value.
https://bugzilla.redhat.com/show_bug.cgi?id=1157641
http://www.ubuntu.com/usn/USN-2409-1
http://www.debian.org/security/2014/dsa-3067
http://www.debian.org/security/2014/dsa-3066
http://support.citrix.com/article/CTX200892
http://secunia.com/advisories/62144
http://secunia.com/advisories/62143
http://secunia.com/advisories/61484
http://rhn.redhat.com/errata/RHSA-2015-0624.html
http://rhn.redhat.com/errata/RHSA-2015-0349.html
http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00019.html
http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=e6908bfe8e07f2b452e78e677da1b45b1c0f6829