CVE-2013-2272 in bitcoind
Summary
by MITRE
The penny-flooding protection mechanism in the CTxMemPool::accept method in bitcoind and Bitcoin-Qt before 0.4.9rc1, 0.5.x before 0.5.8rc1, 0.6.0 before 0.6.0.11rc1, 0.6.1 through 0.6.5 before 0.6.5rc1, and 0.7.x before 0.7.3rc1 allows remote attackers to determine associations between wallet addresses and IP addresses via a series of large Bitcoin transactions with insufficient fees.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 02/25/2019
The vulnerability described in CVE-2013-2272 represents a significant privacy and security flaw within the Bitcoin network's transaction processing mechanisms. This issue affects multiple versions of the Bitcoin reference implementation including bitcoind and Bitcoin-Qt clients, specifically targeting the CTxMemPool::accept method which governs how transactions are accepted into the memory pool. The flaw lies in the penny-flooding protection mechanism that was designed to prevent spam transactions but inadvertently created a mechanism for deanonymization attacks. Attackers could exploit this vulnerability by submitting a series of large Bitcoin transactions with deliberately insufficient fees, effectively creating a method to correlate wallet addresses with IP addresses through the transaction acceptance process.
The technical implementation of this vulnerability stems from the flawed logic within the transaction acceptance algorithm where the system's response to low-fee transactions reveals information about the network's transaction processing behavior. When transactions with insufficient fees are submitted, the system's memory pool management reveals patterns that can be analyzed to establish associations between specific wallet addresses and the IP addresses of nodes that processed these transactions. This occurs because the memory pool's acceptance mechanism does not adequately mask the timing or processing characteristics of transactions that would normally be rejected due to fee inadequacy. The vulnerability operates at the protocol level where the interaction between network nodes and transaction acceptance creates information leakage that can be exploited through statistical analysis and pattern recognition techniques.
The operational impact of this vulnerability extends beyond simple privacy concerns to potentially compromise the fundamental security model of Bitcoin transactions. An attacker could leverage this mechanism to perform address correlation attacks that undermine the pseudonymous nature of Bitcoin transactions, potentially allowing for tracking of user activities across the network. The vulnerability affects not just individual users but the entire network security model as it enables adversaries to map transaction flows and identify potential wallet owners. This information leakage could be particularly damaging when combined with other network analysis techniques or when targeting specific users who maintain multiple wallets or engage in high-value transactions.
The mitigation strategies for this vulnerability involve implementing proper transaction acceptance mechanisms that do not leak information about the processing behavior of the memory pool. Updates to the Bitcoin software versions beyond the specified affected releases would include improved privacy protections within the CTxMemPool::accept method. The fix typically involves ensuring that the transaction acceptance process does not reveal timing information or processing characteristics that could be used to correlate addresses with IP addresses. Network operators should also implement additional privacy measures such as proper transaction relay policies and monitoring for suspicious transaction patterns. This vulnerability aligns with CWE-200 (Information Exposure) and can be categorized under ATT&CK technique T1066 (Credential Access) as it enables adversaries to gather information about network participants that could lead to more sophisticated attacks. The fix demonstrates the importance of privacy-by-design principles in cryptographic protocols and highlights the need for careful consideration of information leakage in security-critical systems.