Attackers may exploit transaction broadcasting to manipulate the sequence of state updates. By sequentially publishing states (e.g., K, K+1, K+2, K+3) at each new block height and offering higher transaction fees, they can potentially override the victim's proposed state update to state N. This tactic hinges on the attacker's ability to ensure their transactions are seen by miners ahead of the victim's without the latter detecting these transactions in the mempool.

The challenge of detecting such deceptive transactions before they are mined underscores a significant vulnerability. The feasibility of this attack largely depends on the attacker's capacity to prevent the victim from observing the malicious transactions in the mempool. This could be achieved by establishing direct connections to the victim's bitcoin node, thereby circumventing traditional detection methods.

However, the implementation of watchtower services offers a robust defense against this attack vector. Watchtowers, acting as independent observers of the mempool, can identify unconfirmed transactions that may affect the user and alert them accordingly. Even a basic arrangement where the watchtower merely monitors the mempool for suspicious activity and notifies the user of potential threats can significantly mitigate the risk of being blindsided by such attacks. This proactive approach to security highlights the importance of external monitoring and intervention systems in safeguarding against sophisticated manipulation tactics in blockchain transactions.