Quote from: bob123 on February 24, 2017, 12:54:10 PM

Quote from: Coin-Keeper on February 21, 2017, 08:39:25 PM

Quote

You should always use a new address every time you receive bitcoins.

Not sure I agree, and for sure know such a practice can add to paperwork in some instances. Example: lets say a website creates a "donation" address (public of course). If 5000 visitors decide to donate to that address OR to 5000 unique address generated by the site, what is the difference? The same coin count is received. There is no security risk since the private keys are not on the site or on the server presenting the public receiving address. The only issue I see is if the site needs to keep records of the individuals sending coins. Therefore it would come down to a business decision in that regard, but not really a security decision. The VPN providers I use are paid via BTC and they generate specific addresses for me to apply my payments when I renew. I understand that because my payments have to be registered against my account, especially since they don't have my name or raw IP to source. I feel the rotation of public addresses is about business conduct and not security. Please feel free to differ. LOL!

In this case.. well alright..
but generally you should use a new address for every transaction.
Multiple situations have been found where more than 1 digital signature can be used to calc the priv key.
The known situations have been fixed.. but there might still be unknown where this is possible..

So its definetly a matter of security.

Could you please explain what do you mean with "more than 1 digital signature can be used to calc the priv key"?
If I sign some messages/addresses with the same wallet (private key) and share the signed message e.g. on the forum (because of proving ownership or for anything else), was it possible in the past to decrypt the private key somehow?
If a wallet provides new public key for every transaction (sendig) does it solve this kind of problem?