Spotting Malicious Injections in Otherwise Benign Code

Being able to spot suspicious code, and then determine whether it is benign or malicious is a very important skill for a security researcher. Every day we scan through megabytes of HTML, JS and PHP. It’s quite easy to miss something bad, especially when it doesn’t visually stick out and follows patterns of a legitimate code.

more here.........http://blog.sucuri.net/2014/10/spotting-malicious-injections-in-otherwise-benign-code.html