Integer overflow in X.org libxcb 1.9 and earlier allows X servers to trigger allocation of insufficient memory and a buffer overflow via vectors related to the read_packet function.
http://www.x.org/wiki/Development/Security/Advisory-2013-05-23
http://www.ubuntu.com/usn/USN-1855-1
http://www.securityfocus.com/bid/60148
http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
http://www.openwall.com/lists/oss-security/2013/05/23/3
http://www.debian.org/security/2013/dsa-2686
http://lists.opensuse.org/opensuse-updates/2013-06/msg00137.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/106752.html