Bitcoin Core Passes Security Audit
In a significant development, Bitcoin Core has passed a rigorous third-party security audit for the first time, underscoring the software’s maturity in maintaining the security of the major decentralized network. This audit, commissioned by OSTIF and executed by the French cybersecurity firm Quarkslab, took place over a 104-day period from May to September and focused on Bitcoin Core’s critical components, including its peer-to-peer (P2P) layer and block validation mechanisms.
Audit Findings
The findings of the audit are notably positive, with the report describing Bitcoin Core’s code as the “most mature and well-tested” in the industry, despite the complexity that comes with a codebase exceeding 200,000 lines of C++ and around 1,200 existing tests. Auditors found no vulnerabilities classified as high or medium severity; they only noted two low-severity issues along with several recommendations to enhance existing testing frameworks primarily associated with fuzzing and coverage improvement. Importantly, the report assured that these findings did not impact the core functionalities related to consensus, resilience against denial-of-service attacks, or transaction validation.
P2P Networking Layer Focus
A particular focus of the audit was on Bitcoin’s P2P networking layer, which plays a crucial role in transmitting blocks, transactions, and in peer discovery, managing approximately 125 connections per node. The reviewers were unable to identify any weaknesses that could allow malicious data to escape validation or to bypass the mechanisms in place which isolate problematic peers. Additional areas scrutinized included the mempool logic and handling of chain-state transitions and network reorganizations. Here too, the audit determined that no exploitable vulnerabilities existed.
Ongoing Debates and Institutional Perspectives
The outcomes of this audit come against the backdrop of ongoing debates between proponents of Bitcoin Core and Bitcoin Knots, sparked by the recent Bitcoin Core v30 update. This dispute revolves around the permissibility of non-financial data on the blockchain, with critics arguing that it could lead to a surge in spam. Supporters of Knots contend that excluding such data is vital to avert illegal or unethical content within Bitcoin’s ledger. Conversely, Bitcoin Core developers contend that imposing limits could fracture network unity, create confusion among users, and contradict the foundational ethos of transparency and neutrality.
Interestingly, despite the contention surrounding this issue, Alex Thorn, head of research at Galaxy Digital, reported that a majority of institutional Bitcoin investors remain relatively unconcerned. Based on his survey of 25 institutional clients, 46% were unaware of the debate, 36% expressed indifference, while 18% aligned themselves with the views of Bitcoin Core.
