Hello. I want to know about any bitcoin offline wallet which includes no third party. And can that wallet be hacked if I don't input any kind of malicious file or connect the device to Internet?
While it is not likely any and all wallets are hackable.
It would be incredible to do it. But generate a correct private key import to your wallet and the address is accessible .
No one has conclusively done this on a cost offline wallet and shown proof they did. But it could happen one day.