Tell me more ×
Cryptography Stack Exchange is a question and answer site for software developers, mathematicians and others interested in cryptography. It's 100% free, no registration required.
up vote 0 down vote favorite

What prevents a miner's block from being accepted across the network if the hash checks out when miner forges transactions in the block?

For example, lets say I'm mining and I want to steal money from address A and put it into my address B. So I build a block with the A->B transaction along with some requested transactions. Now if I can compute a hash for the block before anyone else, and send off to peers in the network, how could they reject it? How would they know that's not a real transaction? Their NAT may have blocked that request or something.

I can't think of a good way of fixing this and I didn't find anything about in documentation. Any insight would be appreciated. Thanks.

share|improve this question
1  
While questions about the cryptographic aspects of Bitcoin (or similar money sistems) are fine here, please note that there is a Bitcoin Stack Exchange where other types of question (such like your one) are better left. I'm not moving your question there since it is already duplicated there (and got a good response). – Paŭlo Ebermann♦ Feb 6 at 20:33

closed as off topic by Paŭlo Ebermann♦ Feb 13 at 9:18

Questions on Cryptography Stack Exchange are expected to relate to cryptography within the scope defined in the FAQ. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about closed questions here.

1 Answer

up vote 4 down vote accepted

All transactions which transfer money from address A need to be signed by the private key for address A which you don't have. The signature of course also covers the destination address B which stops you changing the transaction to redirect the money. The network does not pay attention to blocks which contain invalid signatures.

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.