Transaction Malleability, Mutability

This definition comes from the technical glossary.


The ability of someone to change (mutate) unconfirmed transactions without making them invalid, which changes the transaction’s txid, making child transactions invalid.


  • Transaction malleability

  • Transaction mutability

Not To Be Confused With

  • BIP62 (a proposal for an optional new transaction version that reduces the set of known mutations for common transactions)