Every time you use a key, there is opportunity for the key to get stolen because you are accessing the network using a computer and an internet connection. If your computer gets a virus and hacker knows what to look for, your keys could be compromised if you store them on your computer.
Two things that you can do to keep your money secure:
- Use the active key only when needed
- Store your STEEM in the form of SP or in Savings
The worst thing that can happen if your Posting key is stolen is that the thief could post and vote until you change the key. If a thief steals your active key, they can take any STEEM or SBD that is not stored as SP or in Savings.
Do not store your active key on your computer or phone. Use a removable storage device like a USB drive.