In What Scenario Might an Attacker Try to Manipulate the Raw Transaction Data?

An attacker might try to manipulate the raw transaction data in a scenario involving transaction malleability, before the transaction is confirmed. For example, if a merchant releases goods after seeing an unconfirmed transaction, the attacker could alter the TxID to confuse the merchant's tracking system, potentially leading to a double-spend attempt or denial-of-service against the merchant's wallet software.

This manipulation does not change the transaction's effect but changes its identifier.