I was dubious at first, but I really have grown to like Redis. It’s a wonderfully simple solution to the problem of high-performance fast-changing data storage. However, its simplicity (combined with the incompetency of certain users) can easily become a detriment to security.
The Redis protocol is a simple plain-text mechanism, offering no transport layer security. This is a problem in itself, but it gets worse. By default, it listens on all available IP addresses on port 6379, with no authentication...