The current security models for Bitcoin and Ethereum make 51% and 34% attacks, respectively, “economically unfeasible,” according to a new research paper published on Feb. 15.

A 51% attack is an attempt by an entity to gain control of more than half of a blockchain’s mining hash rate, theoretically allowing it to alter the distributed public ledger maliciously. Similarly, a 34% attack attempts to manipulate the consensus of the ledger (in proof-of-stake or BFT networks) to approve or disapprove specific transactions by acquiring network stake.

According to the researchers, it would have cost an estimated $34.39 billion to 34% attack the Ethereum network on Dec. 31, 2023 — when ether was priced at $2,279 per coin — and it would take until June 14, 2024, for the attacker to successfully …