Recently a vulnerability was found in ImageMagick, which is an image processor that powers a huge part of the web. There's no patch yet, but there is a fix, which I've applied. If anyone notices any weirdness WRT images, let me know!
Details: http://arstechnica.com/security/2016/05/easily-exploited-bug-exposes-huge-number-of-sites-to-code-execution-attacks/#p3