Bitcoin has very strong security the biggest weakness in bitcoin is the user, since you can be deceived and download a wallet infected by malicious code, or a key logger could be used to get your passwords or you could get scammed very easily.
In hacking movies like 'No system is safe' and TV series like 'Mr. Robot', the people have always been the weakness of any secured company. They do social engineering and it's no wonder why even in the bitcoin network, people are still the weak part. I think the reason for this is because humans are the ones controlling the whole thing, they are the one monitoring it. So if you could deceive the user, then you can take over his account.
Anyway, it's kind of easy to avoid this by yourself by having a 2FA on your account. But then again if there's a keylogger or virus on your computer, then you're always doomed to be hacked. I'm using malwarebytes to scan viruses and so far it's all good.