Yes ,cryptocurrency wallets can be hacked even the almighty etheruem wallet/website get hacked all the time.
The easiest way to get hacked is clicking on every link that comes your way.
We need to be very cautious of our wallets so as to avoid being hacked.
hackers now are very smart, they can developt their technique to attack site security.even we have multy layer security, they still able to break and steal our balance.