paperwallet

[nokati]

hi,

If I spend a paper wallet for 100% by sweeping it, is there any danger if you don't destroy the paper and just trow on the street after a couple of confirmations?

Can some one do any harm using the private key of the paper wallet that has been empty?

Thanks

[RappelzReborn]

hi,

If I spend a paper wallet for 100% by sweeping it, is there any danger if you don't destroy the paper and just trow on the street after a couple of confirmations?

Can some one do any harm using the private key of the paper wallet that has been empty?

Thanks

Well if the wallet is empty and there is nothing on it , why you should be worried ? I don't think there is anything to worry about it , however Private keys are important , let's say you own Bitcointalk account and you wanna proove that it's your account you will need that adressso if the private gets in wrong hands he can get your account . (but chances that a Bitcointalk user throw a paper wallet and another bitcointalk user found it again is pretty low ,right ? ) 

[d4n13]

If you swipe the wallet, then spend the outputs here's what happens:

YOU:
1) you import the private key from the paper wallet.
2) you create a transaction to spend the outputs associated with that key.
3) you sign your transaction and send it to whatever node / nodes you are connected to.
4) every node you are connected to sends your transaction to every node they are connected to.
5) very soon a miner sees your tx and scoops it up into whatever block it is mining.
6) various miners around the world do this till miner who finds the magic nonce does so with your block.
7) this miner then submits his nonce (with your tx) and you now have 1 confirmation.

Now IFF right after you swipe your wallet, and walk out, someone picks up the wallet and trys to spend it, the following happens.

OTHER:
1) someone imports the private key from the paper wallet they saw you discard.
2) someone creates a transaction to spend the outputs associated with that key.
3) someone signs thier transaction and sends it to whatever node / nodes they are connected to.
4) every node they are connected to sends your transaction to every node they are connected to.
5) very soon a miner sees thier tx and scoops it up into whatever block it is mining.
6) various miners around the world do this till miner who finds the magic nonce does so with your block.
7) this miner then submits his nonce (with someones tx) and you now have been robbed.

Whoever gets to #7 first gets the money.

So just be all James Bond and burn the paper wallet after you spend

[DannyHamilton]

Corrections below:

- snip -
Now IFF right after you swipe your wallet, and walk out before you have any confirmations at all, someone picks up the wallet and trys to spend it, the following happens.

OTHER:
1) someone imports the private key from the paper wallet they saw you discard.
2) someone creates a transaction to spend the outputs associated with that key.
3) someone signs thier transaction and sends it to whatever node / nodes they are connected to.
4) If the nodes they are connected to have already seen YOUR transaction, then they simply ignore this new transaction.
5) if any nodes they are connected to have not yet seen YOUR transaction, then they send this new transaction to every node they are connected to
6) if those nodes have already seen YOUR transaction, then they simply ignore this new transaction.
7) if there are enough nodes in the system that have not seen YOUR transaction, then eventually a miner sees their tx and scoops it up into whatever block it is mining.
8 ) various miners around the world may do this if your transaction did not relay across the network quickly enough till a miner who finds the magic nonce does so with a block containing one of the two transactions.
9) this miner then submits his nonce (with someones tx) and, if the block contained the the other transaction, you now have been robbed.

Whoever gets to #9 first gets the money.

As you can see, as long as your transaction includes a large enough fee to be properly relayed, and enough seconds have passed for most of the network to have seen your transaction, there is a risk before confirmation but it is very low.  If  you want to avoid that risk completely, simply wait for a confirmation or two.

If you are really paranoid about it, and the address is somehow associated with your identity (such as being used publicly on a discussion forum), then just be all James Bond and burn the paper wallet after you spend

There.  I fixed that for you.

[achow101]

Corrections below:

- snip -
Now IFF right after you swipe your wallet, and walk out before you have any confirmations at all, someone picks up the wallet and trys to spend it, the following happens.

OTHER:
1) someone imports the private key from the paper wallet they saw you discard.
2) someone creates a transaction to spend the outputs associated with that key.
3) someone signs thier transaction and sends it to whatever node / nodes they are connected to.
4) If the nodes they are connected to have already seen YOUR transaction, then they simply ignore this new transaction.
5) if any nodes they are connected to have not yet seen YOUR transaction, then they send this new transaction to every node they are connected to
6) if those nodes have already seen YOUR transaction, then they simply ignore this new transaction.
7) if there are enough nodes in the system that have not seen YOUR transaction, then eventually a miner sees their tx and scoops it up into whatever block it is mining.
8 ) various miners around the world may do this if your transaction did not relay across the network quickly enough till a miner who finds the magic nonce does so with a block containing one of the two transactions.
9) this miner then submits his nonce (with someones tx) and, if the block contained the the other transaction, you now have been robbed.

Whoever gets to #9 first gets the money.

As you can see, as long as your transaction includes a large enough fee to be properly relayed, and enough seconds have passed for most of the network to have seen your transaction, there is a risk before confirmation but it is very low.  If  you want to avoid that risk completely, simply wait for a confirmation or two.

If you are really paranoid about it, and the address is somehow associated with your identity (such as being used publicly on a discussion forum), then just be all James Bond and burn the paper wallet after you spend

There.  I fixed that for you.

Also, if the other person gets sends the transaction with a larger fee, nodes and miners who have implemented replace-by-fee (RBF) will discard your transaction and relay and mine the other one with the larger transaction fee.