Justin Silverton continues his "PHP Security Mistakes" series with this new post, looking at issues surrounding system calls, file uploads, and including files into your scripts.
In one of my previous articles, I mentioned the top 5 security mistakes made in PHP. This article is a follow-up, with some more common security mistakes.
For the three topics he describes the functionality PHP offers for them as well as a suggestion or two as to how you can prevent these issues from showing up in your scripts.