They talk about the tutorial that Wim presented at the ZendCon conference about security and some of his thoughts on why it (security) is becoming more and more important. Cal also asks Wim which vulnerability he sees most often in both older and more current code. They also briefly talk about database security, tips for preventing SQL injection issues by using PDO or abstraction layers and "trust issues" between your application and database contents. They also talk some about the company Wim works for, Cu.be, a PHP consultancy company.
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