Beyond direct hacking, nulled plugins cause long-term damage:
Using a nulled version of OptinMonster 2.17 or any other plugin can lead to: nulled wordpress optinmonster 217 plugin
OptinMonster is a powerhouse for lead generation, using a "nulled" (pirated) version of any WordPress plugin carries significant risks that often outweigh the benefits of getting premium features for free. The Risks of Nulled Plugins Beyond direct hacking