This paper explains how combining Bitcoin and Tor creates an attack vector. A man in the middle can control the information flow between all users who connect over Tor. This paper is from 2014. Has this sort of risk been mitigated by new engineering yet?
1 Answer
Version 2 P2P transport probably fixes at least part of this as it encrypts the traffic between Nodes.
From the paper:
An obvious countermeasure would be to encrypt and authenticate Bitcoin traffic. This would prevent even opportunistic man-in-the-middle attacks (i.e. even if the user is unlucky to choose the malicious Exit relay). - IX. COUNTERMEASURES
The Motivation paragraph of BIP324 addresses this: https://github.com/dhruv/bips/blob/bip324/bip-0324.mediawiki#user-content-Motivation
More ressources on BIP324: https://bitcoinops.org/en/topics/v2-p2p-transport/
