Routing Attacks Against Pub/Sub Blockchain Networks

Abstract

Sophisticated threat actors have begun utilizing the network layer in an attempt to disrupt blockchain networks and their applications. These cross-layer attacks have impacted centralized exchanges, decentralized applications, wallets, miners, and more with the intent of stealing from or defrauding blockchain users. At the same time these sophisticated attacks are being developed, blockchain technology has become increasingly more complex. While Bitcoin has remained relatively untouched, other networks like Ethereum have shifted towards Proof-of-Stake (PoS) based consensus with long term plans of becoming a sharded network. These fast-paced and recent developments have resulted in complex and actively deployed systems with little understanding as to what risks may exist in the cross-layer.

This thesis serves a dual-purpose: both as an extremely technical illustration of how these more sophisticated blockchain networks are being developed as well as a heuristic analysis of what threats may exist in the cross-layer. This thesis explores a more recent blockchain optimization known as peer-to-peer publish/subscribe (Pub/Sub) messaging and how routing attacks may impact it. The risks associated with Pub/Sub messaging have significant implications for the design and security of sharded blockchain networks. Therefore, this seminal work is a crucial topic for future blockchain development. While the heuristic analysis in this work focuses on Ethereum, we emphasize that these analysis techniques and their implications are relevant for all forms of peer-to-peer Pub/Sub blockchain networks.