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Bitcoin => Bitcoin Discussion => Topic started by: BTCBinary on November 10, 2015, 05:00:01 AM



Title: Malleability attack explained
Post by: BTCBinary on November 10, 2015, 05:00:01 AM
Lately, i've been hearing a lot about the bitcoin malleability attack. Unfortunately I didn't quite understand what's that all about.

Can anyone give a simple a good explanation?


Title: Re: Malleability attack explained
Post by: AgentofCoin on November 10, 2015, 05:11:44 AM
Lately, i've been hearing a lot about the bitcoin malleability attack. Unfortunately I didn't quite understand what's that all about.

Can anyone give a simple a good explanation?


Simply, when you broadcasted your tx, there was a possibility that a script written by the "attacker" would see your tx, copy it, mal-form it,
and broadcast that malformed version. What would then happen is that it seemed as if you attempted a double spend, when you didn't.
Sometimes due to this malformed broadcasted tx, certain wallets worked incorrectly and certain businesses waited longer for confirms,
and people generally got nervous.

In reality, it caused no actual damage to the bitcoin ecosystem and was just a nuisance.
Your tx would eventually confirm and your funds would go to the proper address you provided, eventually.

I'm not 100% sure, but my understanding is the protocol has been updated to prevent this now. Certain wallets may still be vulnerable though.



Title: Re: Malleability attack explained
Post by: Kakmakr on November 10, 2015, 05:41:20 AM
I think the best explanation and answers for this attack and the impact it has and a possible solution could be found here : https://bitcoinmagazine.com/articles/the-who-what-why-and-how-of-the-ongoing-transaction-malleability-attack-1444253640 It was also discussed in detail here : http://www.coindesk.com/bitcoin-bug-guide-transaction-malleability/

Hope that helps you.  ;D