TechFlow reports that regarding the malicious behavior where "buyers initiate inscription purchases with extremely low Gas fees, causing transactions to remain unconfirmed in the short term, then accelerating transactions when prices rise or canceling them when prices fall," SlowMist founder Yu Xian stated on X that due to the PSBT signing mechanism used by trading platforms, such transactions can indeed maliciously occupy a transaction slot for a certain period.
Using RBF can accelerate transaction confirmation, but it does not accelerate transaction cancellation (what gets canceled is actually the previous low-fee transaction before confirmation; theoretically, there will eventually be a successful transaction according to the seller's PSBT agreement).
Yu Xian noted that such an offer could be occupied for a long time (for example, several days), but continuously holding it indefinitely is not allowed by the Mempool, although he is currently unsure of the exact duration. Therefore, platforms must implement timeout mechanisms to prevent sellers' PSBT signatures from being occupied indefinitely. Once timed out, other buyers should be allowed to take over and use the seller's PSBT signature.
