1

I want to replicate transaction malleability to study it.

I have two transactions data signed in testnet. One it's the original,

0200000001abb6c7df544b53eec11612ab9d82ef0fe0a3aa2ff33f41bbf5f149986d80af47000000006a47304402207a325de81b063d3e28023a63c37c554e7eb136d94612334bbd6715a05abb684e02203a87c85819815bb12d4386fa76aa6b990c65158b61ccb05a14a249e14095663b012103bf7b2ddadda97523405400ae95be2cb153768cce8b1bed55d1c8aca4bb2ee16dffffffff02e8030000000000001976a914fd1002f92de062322225735e24b85590a3ef7af288ac29e31100000000001976a9146162f487e0b293054f1fb8025769f1e1f14d379b88ac00000000

The second one is the transaction "malleated".

0200000001abb6c7df544b53eec11612ab9d82ef0fe0a3aa2ff33f41bbf5f149986d80af47000000006c527547304402207a325de81b063d3e28023a63c37c554e7eb136d94612334bbd6715a05abb684e02203a87c85819815bb12d4386fa76aa6b990c65158b61ccb05a14a249e14095663b012103bf7b2ddadda97523405400ae95be2cb153768cce8b1bed55d1c8aca4bb2ee16dffffffff02e8030000000000001976a914fd1002f92de062322225735e24b85590a3ef7af288ac29e31100000000001976a9146162f487e0b293054f1fb8025769f1e1f14d379b88ac00000000

Before send the first one and after send the malleated transaction.

I receive txn-mempool-conflict (code 18)

I can't replicate the transaction malleability if the original is already in the mempool?

I'm using bitcoin-core 0.19.0.1

Improve this question

1 Answer 1

Reset to default
2

What malleability means is that you can create a transaction that is identical in its meaning (same inputs, same outputs) but with a different TXID. That is problematic for 2nd layer protocols where transactions build onto each other but aren't necessarily published to chain.

But a "malleated" transaction is still a double spend. And it appears newer versions of bitcoin-core that support RBF won't accept double spends into their mempool.

See code snippet here: Validation Error: Error #-26: 258: txn-mempool-conflict

Improve this answer
3
  • Thanks @guggero, Can I disable RBF in my node? I don't find any option
    – monkeyUser
    Jan 16, 2020 at 16:06
  • RBF (as specified in BIP125) only applies when you signature replacement. The problem is here that you don't do that, and as a result the replacement is not accepted.
    – Pieter Wuille
    Jan 16, 2020 at 16:32
  • This is unrelated to RBF. Double spends have never been accepted.
    – Andrew Chow ♦
    Jan 16, 2020 at 16:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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