Relay Censorship
Relay censorship occurs when the entities responsible for passing blocks between builders and validators intentionally exclude certain transactions from the blocks they relay. In the MEV-Boost architecture, relays act as trusted intermediaries that verify block validity and ensure builders pay the promised rewards to validators.
If a relay is compromised or operates with malicious intent, it can filter out transactions from specific addresses or protocols, effectively censoring them from the blockchain. This behavior violates the principle of censorship resistance, which is fundamental to the security and neutrality of decentralized networks.
When censorship happens at the relay level, it can prevent users from interacting with specific decentralized applications or accessing their funds. This creates a significant risk, as it concentrates power in the hands of a few relay operators who can dictate which transactions are allowed to reach the consensus layer.
Mitigating this requires decentralized relay architectures and increased transparency in how blocks are processed and validated.