A "nulled" version is an illegal copy of the software that a pirate is making available for download. You can put yourself and your site at serious legal risk by using a "nulled" version of any software product.
Apart from any legal issues using a "nulled" ie unlicenced board with software obtained elsewhere, it may well contain extra unwanted code that could both compromise your community and / or server. As I say aside from the legal point itself, they are really not work the risk of running.
@grande_ecks esti grav , prietene , zi-mi unde scrie aici ceva de vulnerabilitati , nu de backdoor-uri
@gadeas Toate celalalte chestii ce se intampla, dexemplu un exploit, astea se pot intampla si pe software-ul original cu tot cu licenta, sa nu credeti ca exploit-urile exista doar pe variantele nulled. CORECT.