发表机构
Sun Yat-sen University; The Hong Kong Polytechnic University; Zhejiang University（中山大学; 香港理工大学; 浙江大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对跨链桥破坏交易追踪的问题，提出证据驱动系统XSplicer，利用公开协议规范重建跨链交易对应关系，在七个协议上实现92.5%恢复率，并成功应用于真实案件。
AI 中文摘要
跨链桥实现了互操作性，但也切断了追踪非法资金所需的交易踪迹。第三方调查人员通常无法访问桥接后端维护的源到目标映射，而我们对131个桥的调查发现，只有16.79%的桥提供完整的公开追踪。现有方法依赖于官方API、EVM特定假设或脆弱的时序启发式方法，限制了其在异构账本上追踪转账的能力。我们提出了XSplicer，一个证据驱动的系统，用于在无需桥接后端特权访问的情况下重建跨链交易对应关系（xTCR）。XSplicer从公开协议文档和交易示例中推导出统一的语义规范，将其转化为轻量级解析器和验证器，并通过优先考虑硬证据、仅在必要时使用软线索来关联源交易和目标交易。我们在涵盖EVM、Bitcoin和Solana的七个桥协议上评估了XSplicer。XSplicer实现了92.5%的全局恢复率，在单个协议上最高可达98.61%。在对抗性噪声下，其硬证据验证器在100%的测试案例中保留了正确的匹配，而软线索匹配随着模糊性增加而退化。在两个真实世界案例研究中，XSplicer在Multichain停止运营后恢复了超过1,900个历史交易对，并在Bybit洗钱事件中识别出754笔价值1.056亿美元的非法跨链转账。这些结果表明，公共协议不变量可以在没有特权桥映射的情况下支持实用的跨链取证。
英文摘要
Cross-chain bridges enable interoperability, but they also break the transaction trails needed to trace illicit funds. Third-party investigators typically cannot access the source-to-destination mappings maintained by bridge backends, and our survey of 131 bridges finds that only 16.79% provide complete public tracking. Existing approaches depend on official APIs, EVM-specific assumptions, or fragile temporal heuristics, limiting their ability to trace transfers across heterogeneous ledgers. We present XSplicer, an evidence-driven system for reconstructing cross-chain transaction correspondence (xTCR) without privileged access to bridge backends. XSplicer derives unified semantic specifications from public protocol documentation and transaction examples, translates them into lightweight parsers and verifiers, and links source and destination transactions by prioritizing hard evidence and using soft clues only when necessary. We evaluate XSplicer on seven bridge protocols spanning EVM, Bitcoin, and Solana. XSplicer achieves 92.5% global recovery rate and up to 98.61% on individual protocols. Under adversarial noise, its hard-evidence verifier retains the correct match in 100% of tested cases, while soft-clue matching degrades as ambiguity increases. In two real-world case studies, XSplicer recovers more than 1,900 historical transaction pairs after Multichain ceased operations and identifies 754 illicit cross-chain transfers worth 105.6 million USD in the Bybit laundering incident. These results show that public protocol invariants can support practical cross-chain forensics without privileged bridge mappings.
