Former Ripple Labs CTO (Chief Technology Officer) David Schwartz has downplayed the potential risks from front-running attacks on the XRP Ledger (XRPL) network, which uses XRP as its native token.
On June 29, Schwartz addressed ongoing community concerns about transaction front-running and sandwich attacks. The former Ripple CTO replied to X user XRPresso, who raised an issue about an attack vector affecting decentralized exchange (DEX) and automated market maker (AMM) trades on the XRPL network.
“Concerns have been raised about the possibility of front-running or transaction sandwich attacks on XRPL payments and offer crossing… I’m not that concerned about this issue,” Schwartz stated.
A front-running attack could occur when a rogue validator node sees a pending transaction in the pre-validation queue before the ledger closes and opts to insert their own transactions ahead of the original XRPL request.
Nonetheless, Schwartz acknowledged that these risks exist in theory but said he is not overly concerned in practice. As such, he offered a concrete reservation-based mitigation scheme to eliminate the attack vector for those who want protection.
“I have a proposal for a fairly simple scheme that would eliminate this attack. It’s a transaction reservation scheme that can ensure that a transaction executes before any transaction that was formed after it was disclosed,” Schwartz added.
Details of proposed solutions for sandwich attacks on XRPL from Ripple CTO
Schwartz proposed a new ledger object dubbed ReservedTxns, which would store a list of transaction IDs assigned to a specific future ledger. As a result, XRPL users can reserve a transaction slot up to 16 ledgers in advance by submitting a TxnReserve transaction and paying at least twice the standard fee.
He added that the reserved transaction would be broadcast at a precisely timed moment after key consensus information from the previous ledger becomes known. This timing reduces the opportunity for attackers to react before the original transaction.
Furthemore, when the target ledger is executed, these reserved transactions would be processed with priority ahead of the normal transaction queue. While the former Ripple CTO does not believe front-running is a major threat today, the reservation system provides users with an optional strong layer of protection for high-value, time-sensitive transactions on the DEX and AMM.
