Tutorial shows you how to clean a nulled Wordpress theme. Remove viruses and malware from wordpress themes nulled themes. Themes downloaded from sites that offer free premium (freemium) themes are normally infected by viruses.
There are online sites that detect malicious code (eg virustotal.com). But just as a principle all nulled themes somehow contain malicious codes. Never trust any.
what if i have a nulled theme and the class.theme-modules.php isn't there at all? the functions.php file doesn't have that on top. is there another way to infect these themes?
Then it may not be infected but to be sure that it isn't, you can upload the zip file to virustotal.com and you see the results they give you! Incase of any more questions, you can let me know,