Found an interesting article over at OttoPress with some in depth analysis of malware discovered in a theme on a less than reputable WordPress theme site. Seems there are some dodgey sites out there that have infected themes, both free ones and ripped off professional themes. Beware and check the reputation of your themes.
It had malware inserted into it that is of a much more malicious and spammy nature. Further investigation reveals that ALL of the themes on that site contain basically the same code. This code is not actually “viral”, but it’s definitely malware and it’s worth investigating to see some of the ways people try to hide their spam.
So today, I’m going to dissect it and serve it up on a platter for everybody to see.
Other excellent posts on this topic include:
Jaypee writes on WordPress Theme Malware
Analysis of Top Google Results for Free WordPress Themes