MySQL 5.1.x before 5.1.63 and 5.5.x before 5.5.24 allows remote authenticated users to cause a denial of service (mysqld crash) via vectors related to incorrect calculation and a sort order index.
https://bugzilla.redhat.com/show_bug.cgi?id=833737
http://www.securityfocus.com/bid/55120
http://www.mandriva.com/security/advisories?name=MDVSA-2013:150
http://security.gentoo.org/glsa/glsa-201308-06.xml
http://secunia.com/advisories/53372
http://secunia.com/advisories/51309
http://rhn.redhat.com/errata/RHSA-2013-0180.html