Question about replay attack...am I safe?? (BTG Hard Fork)

[speedstickman]

Hi, so l'm still trying to wrap my head around this concept of replay attacks and replay protection. As far as I understand, most advice comes down to... your keys, your coins. So as long as you hold your own keys , you are safe.

I had some bitcoin in coinbase that I transferred to my Trezor AFTER the bitcoin GOLD hard fork... am I in danger of a replay attack? if so, how can I protect myself?


Any help and advice is much appreciated... thank you

[jekjekman]

Hi, so l'm still trying to wrap my head around this concept of replay attacks and replay protection. As far as I understand, most advice comes down to... your keys, your coins. So as long as you hold your own keys , you are safe.

I had some bitcoin in coinbase that I transferred to my Trezor AFTER the bitcoin GOLD hard fork... am I in danger of a replay attack? if so, how can I protect myself?


Any help and advice is much appreciated... thank you

I am not so professional about this Bitcoin technical aspects but I can assure that as long as you only transacting with your Bitcoin address/adresses online and never give your private key or seed to anyone and accidentally post in everywhere then you are safe unless someone really breach with your own personal computer that gain access to your important files.

Transferring funds from an online wallet to your hardware wallet is safe though because the only thing that has been publicly showed is your Bitcoin address.

[odolvlobo]

I had some bitcoin in coinbase that I transferred to my Trezor AFTER the bitcoin GOLD hard fork... am I in danger of a replay attack?

First, a replay attack is not really an "attack". It is simply describes when a transaction intended for one chain occurs on both (because nothing was done to prevent that from happening).

If you sent BTC from Coinbase after the fork, then you may or may not have also received BTG. It depends on whether the Coinbase address has BTG and whether they prevented replay or not.

If Coinbase does not prevent replay, then it is possible to suck BTG out of Coinbase. Simply send BTC to Coinbase using replay protection, and then withdraw the BTC back to your wallet. Assuming that Coinbase does not prevent replay, any time BTC is sent to you from an address that also has BTG, you will get the BTG, too.

[gyu22]

Some tips to protect yourself from replay:
People Can Send Non-Replayable Transactions, But the Methods Are Not For the Light Hearted 

Coinbase Transaction

There are some ways users and miners can send transactions and still keep a level of replay protection. The methods require specialized software and a reasonable level of technical knowledge. For instance, miners or people who know a mining pool can utilize sending bitcoins by a ‘Coinbase transaction’ which cannot be replayed after the fork. This is one method where an individual or group can send non-replayable transactions, but there’s a catch. Bitcoins in a Coinbase transaction cannot be spent until they’ve received 100 confirmations. But they will be only valid on the chain they were originally generated from, which assures there will be no replay for those UTXOs.

nLocktime

Another method which requires a bit of technical knowledge and software that can accomplish the process is called, ‘nLocktime.’ This procedure means when the two chains bifurcate, a transaction can be set for a specific time or block height. A user can use a full node client to set the nLocktime to a block height, but there are not that many wallets that offer this feature. By utilizing the nLocktime method, a user can essentially create a transaction that will confirm on the longest chain.

Two Transactions — Two Fee Settings

Bitcoin developer, David Harding, explains another process of using two different fees for transactions on both the high fee chain and the low fee chain. The statement from Harding is a response to a question from the CEO of Coinbase, Brian Armstrong, asking about replay prevention on the Bitcoin Stack Exchange Q&A website. 

“It is possible miners on one side of the fork may be mining transactions with lower fees than on the other side, so you can broadcast a low-fee version of your transaction on the low-fee chain, wait for it to confirm, and then broadcast a higher-fee version on the high-fee chain,” explains Harding.

https://news.bitcoin.com/a-look-at-bitcoin-replay-attacks-and-self-managed-utxo-protection/