SPV Merkle proof malleability allows the maintainer to prove invalid transactions
Summary By publishing specially crafted transactions on the Bitcoin blockchain, the SPV maintainer can produce seemingly valid SPV proofs for fraudulent transactions. The issue was originally identified by Least Authority in the tBTC Bridge V2 Security Audit Report as Issue B: Bitcoin SPV Merkle Proofs Can Be Faked. A mitigation was believed to have been in place, but this turned out to contain an error, and the issue had not …