Researchers say Ripple’s protocol “could seriously fail”

Researchers from the University of Bern have published a report stating that Ripple’s consensus protocol “guarantees neither security nor liveliness”.

In a blog published yesterday by the university’s Cryptology and Data Security Research Group, researchers Christian Cachin, Amores-Sesar and Jovana Mićić published an analysis that the payment company’s consent protocol could allow users to potentially “spend twice a token “and stop processing transactions.

The trio created examples of the Ripple protocol using different numbers and types of nodes to illustrate possible breaches of security and life (a term for the network that continues to process transactions and make progress). According to their models, the presence of bad or malicious nodes could have “devastating effects on network health”.

“Our results show that the Ripple protocol relies heavily on synchronized clocks, timely message delivery, the presence of an error-free network, and prior agreement on trusted nodes common with the [Unique Node List] signed by Ripple, “the researchers said.

“If one or more of these conditions are violated, especially if attackers are activated within the network, the system may malfunction.”

David Schwartz, Ripple’s chief technology officer, quickly he answered to Cachin on Twitter disputing the results. Ripple’s CTO sustained such a situation was “impractical”, stating that any attacker would have to “partition the network” and check part of its unique node list, or UNL, to do as proposed by the researchers.

I welcome documents like this one and appreciate that any weaknesses have been identified and reported. Any opportunity to improve the XRPL consensus protocol or blockspace security and reliability is generally a good thing. 1/8

– David Schwartz (@JoelKatz) December 3, 2020

“The general philosophy of the UNL is that the attackers have a chance to put their lives in danger and then they are forever out of the UNL,” Schwartz said. He added:

“Security attacks also require significant control over the propagation of messages over the network, which makes them impractical. This is why Bitcoin’s total lack of partition tolerance is not a practical problem. “

None of the researchers have yet responded to Ripple’s CTO criticism of their findings. The group admitted in the original analysis that the attacks were “purely theoretical and have not been demonstrated with a live network”.