Bitcoin Forum

Hello:
someone I know his bitcointalk talked got hacked or something. his email and password got changed.
there is a post that says if your account gets hacked you should PM an admin with this message:


Can someone please explain to me this?

BEGIN BITCOIN SIGNED MESSAGE
BEGIN SIGNATURE
<insert address here>
<insert signature here>
END BITCOIN SIGNED MESSAGE
 Thank you.

He had to post some of his addresses some time publicly and  because he can sign a message then he claims that he is indeed the real owner if we say that only he had the private key and it wasn't leaked or something.

Anyway here is a good post, I'll advise you to read the documentation and if you have questions ask : https://bitcointalk.org/index.php?topic=990345.0

Thank you for the respond but in the article I found they said


What if you don't have a bitcoin address associated with your account? does that mean you can't prove your ownership of the account? 

You could also sign a message via PGP, but if you don't have any of these then you cannot provide sufficient evidence. I'm sure if you are participating in a Bitcoin forum you would have a Bitcoin address which was posted either publicly or privately via a personal message especially if you've been here for awhile.

No other method is accepted.

He never used his bitcoin address here, he only used his MEW address.

For Future Reference (Prevention is better than a cure):

You can easily get one associated with your account, https://bitcointalk.org/index.php?topic=996318.0 , that is the thread that almost everyone uses to "stake" their address; which means you post an address that you and only you have the private key to with a signed message in your post for verification. Someone will then quote your post, signed message and they will make sure that your message is verifiable to prove your ownership of that address. At that point, anytime there is any question of ownership of your bitcointalk account you can easily produce a new signed message from your staked address and there will be no reasonable doubt that you are the owner. Obviously, this puts a level of pressure on keeping your private key and that particular address protected; never lose this. It would be preferable that this address be a cold-storage address that is not at risk of being key-logged or infected by a virus being on your computer for regular usage.

If you do not stake an address your bitcointalk account will have one less measure to prove that it is in fact yours; without this verification I believe it is next to impossible to ever recover your account if it is hacked, you lose your password or get locked out for any other obscure reason (security questions do this, for example). Essentially, no you will not be able to provide sufficient proof of ownership over your account without associating an address, signing a message and keeping it private.

For Now:

If your friend has not staked an address there, they must have used another address around the forum somewhere? If this is the case, it would probably be sufficient to sign an address they've used publicly around the forum.


Are they able to sign their MEW address?

They might accept that if he can sign a message with it. It might be worth signing a message with it and sending a message to cyrus/theymos. I believe I've seen hilariousandco say that they accept ETH signatures and as long as MEW follows the same system of signing and verifying they may accept it.

If he still has access to that MEW wallet I think it should count as valid reference since ethereum is also based on priv and pub keys. Just signing a message then is a bit different but nothing to much different.

Here is a tutorial on how to sign a message with MEW: https://blog.chronologic.network/sending-a-signed-message-from-your-myetherwallet-332e73066f98