Unspecified vulnerability in the Server component in Oracle MySQL 5.1.66 and earlier and 5.5.28 and earlier allows remote authenticated users to affect availability via unknown vectors related to Server Optimizer.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A17268
http://www.ubuntu.com/usn/USN-1703-1
http://www.oracle.com/technetwork/topics/security/cpujan2013-1515902.html
http://security.gentoo.org/glsa/glsa-201308-06.xml