Unspecified vulnerability in the MySQL Server component in Oracle MySQL 5.5.19 and earlier allows remote authenticated users to affect availability via unknown vectors related to Server Optimizer.
MySQL Community Server 5.0.x before 5.0.51, Enterprise Server 5.0.x before 5.0.52, Server 5.1.x before 5.1.23, and Server 6.0.x before 6.0.4, when a table relies on symlinks created through explicit DATA DIRECTORY and INDEX DIRECTORY options, allows remote authenticated users to overwrite system table information and gain privileges via a RENAME TABLE statement that changes the symlink to point to an existing file.