Eclipsing Bitcoin Nodes with BGP Interception Attacks

The discussion focuses on the effectiveness of countersigns in preventing man-in-the-middle (MITM) attacks, particularly in the context of Bitcoin transactions and block propagation. The scenario highlighted involves an attacker intercepting connections to a mining pool gateway, with the capability to delay or drop traffic, thereby censoring transactions or blocks. This situation underscores the potential for attackers to undermine network integrity by targeting specific nodes within a cryptocurrency's blockchain.

The adoption of BIP324 and StratumV2 protocols is recommended to mitigate such risks, suggesting these technologies limit the damage an attacker can inflict. The conversation also delves into the use of alternative connection methods like Tor and I2P. It is posited that while multiple Tor peers could theoretically simplify an attack if a single entry guard is consistently exploited throughout the ordeal, diversifying or frequently rotating entry guards across one Tor connection would complicate such efforts. I2P's approach, forming short-lived tunnels with a broader peer set, could offer more resilience against attacks compared to Tor.

Further, the exchange touches on the topic of network engineering and the absence of widespread detection mechanisms for such attacks beyond ROA/RPKI and custom filters or monitoring. The possibility of employing aggressive probing and anomaly detection techniques as countermeasures is discussed, referencing literature on the volume of announcements for detecting anomalies. Moreover, the dialogue explores how the classic eclipse attack may be facilitated under certain conditions but also acknowledges the complexities involved in poisoning addrman’s tables due to the equitable treatment of outbound and inbound connections in terms of received ADDR messages.

The conversation shifts toward technical strategies for detecting and mitigating interception attacks, highlighting the utility of traceroutes in identifying anomalous route consolidations through adversarial autonomous systems (AS). A suggestion is made to perform additional traceroutes to peers not traversing the attacker AS as a reactive measure. The discussion also considers the limitation of traceroutes for inbound connection hijacks and the necessity for external cooperation or vantage points to detect such breaches effectively.

Lastly, raising awareness about these security vulnerabilities and the current adoption rate of Address Specific BGP Hijacking Protection (ASPA) objects among node prefixes is underscored as immediate and actionable. Despite the low coverage of node prefixes by ASPA objects, the dialogue concludes with an interest in modeling ASPA adoption and assessing its potential in enhancing security against network attacks.