Recently my site has been infected with malicious codes. All PHP files have been edited by the hacker. He added a bunch of codes to every single PHP file in my server, including Xenforo installation. I have trouble with the backup and now I'm thinking the only possible solution apart from editing all PHP files one by one: replacing all PHP files with new ones I obtain from my fresh Xenforo installation folder. Will be it safe and will there be any impacts on the forum's functionality?