Four days ago I received an email from Dawid Golunski through the list illustrating one of the more brutal pair of security vulnerabilities I have seen recently. Here's how it works. The exploit uses a vulnerability within MariaDB, PerconaDB (and/or XtraDB Cluster) and MySQL to, first, gain access to the 'mysql' system user using any mysql user that has CREATE / INSERT / UPDATE permissions. The first part revolves around a race condition when sql generates temporary files as part of the `REPAIR table` command. Then using the mysql system user the second vulnerability grants the attacker root access to the server using a clever hack that takes advantage of mysql_safe's approach to writing to file based error logs. Below I've provided a list of vulnerable server versions. Just about any server using the more recent (unpatched) stable releases of MySQL or MariaDB through CentOS is vulnerable (Percona isn't part of the st
Server admin, curmudgeon.