Bitcoin Core released a new software update Wednesday, Bitcoin Core 0.20.0. Notably, the release includes experimental software to hedge against attacks from players the size of nation-states, which could effectively fracture the Bitcoin network.
Called “Asmap,” this new configuration protects the peer-to-peer architecture of bitcoin nodes by mapping connections to Tier 1 or larger Tier 2 Autonomous Systems (AS) – internet operators capable of connecting to multiple networks with defined routing plans such as Amazon Web Services or states – and then “limiting the connections made to any single [AS].”
In essence, the so-called “Erebus” attack allows an AS to censor large swaths of the Bitcoin network by limiting and then spoofing peer-to-peer (P2P) connections. Failure to address the flaw could lead to highly undesirable consequences for Bitcoin such as a major mining pool or exchange being cut off from the rest of the network.
An Erebus attack was first hypothesized by researchers at the National University of Singapore (NUS) – Muoi Tran, Inho Choi, Gi Jun Moon, Anh V. Vu and Min Suk Kang – who co-authored a 2019 paper detailing the attack.
The kicker? It’s entirely undetectable until too late.
Erebus falls under the general “man-in-middle” attack scheme made possible through the P2P nature of bitcoin. Greek for “shadow,” Erebus is itself a derivative of the “Eclipse” attack first described in 2015.
As theorized, the malicious actor will try and connect t...