Author: Adam Back 2013-05-06 22:51:46
Published on: 2013-05-06T22:51:46+00:00
In this email thread from 2013, Gregory Maxwell and Adam Back discuss the vulnerability of Bitcoin network attacks. Back believes that Bitcoin's primary vulnerability is network attacks to induce network splits, which can be fooled into accepting an orphan branch as the one-true block chain. Maxwell points out that it currently costs six million dollars to reduce the difficulty in an isolated fork by a factor of four. Back suggests hacking a pool to co-opt it into his netsplit or segmenting enough of the network to have some miners in it, and they do the work. He also mentions that malware could do the same thing for clients. Protecting against such attacks is the biggest continued justification for checkpoints.Back also notes that most binaries and tar balls are not signed nor served from SSL - at least for Linux. However, Maxwell claims that they are signed. Back refutes this claim and points out that he does not see any signatures for Linux and none in the tarball. There are some public keys inside the tarball, but that is it. Even if there is code signing on the Windows exe, the user does not know that, nor who they should be signed by, and as they are served via HTTP, it's bypassable. The easiest way to attack right now is just to change the binaries to create a user-operated netsplit, or just have all their wallets empty to you via a mix once the amount gets interesting.
Updated on: 2023-06-06T16:16:50.756852+00:00