A Proposed Algorithm for Detecting Mixers in Ethereum
Abstract
This work presents a methodology for detecting smart contracts of the mixer type on the Ethereum network. A machine learning model based on Random Forest was employed, trained with transactions from Tornado Cash and balanced with samples from 100 randomly selected addresses unrelated to mixers. The model was trained using data from March 2025 and validated on October 29, 2020—a day with high transaction volume—successfully identifying 3 Tornado Cash addresses.References
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Shojaeenasab, A., Motamed, A. P., and Bahrak, B. (2022). Mixing detection on bitcoin transactions using statistical patterns.
Tang, Y., Xu, C., Zhang, C., Wu, Y., and Zhu, L. (2022a). Analysis of Address Linkability in Tornado Cash on Ethereum, pages 39–50.
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Tironsakkul, T., Maarek, M., Eross, A., and Just, M. (2020). Tracking mixed bitcoins.
Victor, F. and Weintraud, A. M. (2021). Detecting and quantifying wash trading on decentralized cryptocurrency exchanges. In The Web Conference 2021 - Proceedings of the World Wide Web Conference, WWW 2021, pages 23–32. Association for Computing Machinery, Inc.
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Wang, Z., Chaliasos, S., Qin, K., Zhou, L., Gao, L., Berrang, P., Livshits, B., and Gervais, A. (2023b). On how zero-knowledge proof blockchain mixers improve, and worsen user privacy. In ACM Web Conference 2023 - Proceedings of the World Wide Web Conference, WWW 2023, pages 2022–2032. Association for Computing Machinery, Inc.
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Xu, C., Xiong, R., Shen, X., Zhu, L., and Zhang, X. (2023). How to find a bitcoin mixer: A dual ensemble model for bitcoin mixing service detection. IEEE Internet of Things Journal, 10:17220–17230.
Youn, M., Chin, K., and Omote, K. (2023a). Empirical analysis of cryptocurrency mixer: Tornado cash. In 2023 Congress in Computer Science, Computer Engineering, Applied Computing (CSCE), pages 2324–2331.
Youn, M., Chin, K., and Omote, K. (2023b). Empirical analysis of cryptocurrency mixer: Tornado cash. In Proceedings - 2023 Congress in Computer Science, Computer Engineering, and Applied Computing, CSCE 2023, pages 2324–2331. Institute of Electrical and Electronics Engineers Inc.
Ziegeldorf, J. H., Grossmann, F., Henze, M., Inden, N., and Wehrle, K. (2015). Coinparty: Secure multi-party mixing of bitcoins. In Proceedings of the 5th ACM Conference on Data and Application Security and Privacy, CODASPY ’15, page 75–86, New York, NY, USA. Association for Computing Machinery.
Zola, F., Medina, J. A., Venturi, A., and Orduna, R. (2025). Topological analysis of mixer activities in the bitcoin network.
(2023). Blockchair: Universal blockchain explorer and api. Accessado: 2 de Maio, 2025.
(2024). Tornado.cash: 10 eth mixer contract. [link]. Acesso em: 15-Mar-2025.
Breiman, L. (2001). Random forests. Machine Learning, 45(1):5–32.
Brownworth, A., Durfee, J., Lee, M. J., and Martin, A. (2024). Regulating decentralized systems: Evidence from sanctions on tornado cash. Technical report, Federal Reserve Bank of New York.
Béres, F., Seres, I. A., Benczúr, A. A., and Quintyne-Collins, M. (2020). Blockchain is watching you: Profiling and deanonymizing ethereum users.
Du, H., Che, Z., Shen, M., Zhu, L., and Hu, J. (2024). Breaking the anonymity of ethereum mixing services using graph feature learning. IEEE Transactions on Information Forensics and Security, 19:616–631.
Ermilov, D., Panov, M., and Yanovich, Y. (2017). Automatic bitcoin address clustering. In 2017 16th IEEE International Conference on Machine Learning and Applications (ICMLA), pages 461–466.
Etherscan Blockchain Explorer. Etherscan blockchain explorer. Acesso em: maio de 2025.
Gomez, G., Moreno-Sanchez, P., and Caballero, J. (2022). Detecting cybercriminal bitcoin relationships through backwards exploration.
Kappos, G. and Piotrowska, A. M. (2019). Extending the anonymity of zcash. pages 5–6.
Mariani, J. and Homoliak, I. (2025). Sok: A survey of mixing techniques and mixers for cryptocurrencies.
Meiklejohn, S. and Mercer, R. (2018). Möbius: Trustless tumbling for transaction privacy. Proceedings on Privacy Enhancing Technologies, 2018(2):105–121.
Nadler, M. and Schär, F. (2023). Tornado cash and blockchain privacy: A primer for economists and policymakers. Federal Reserve Bank of St. Louis Review, 105:122–136.
Nakamoto, S. (2008). Bitcoin: A peer-to-peer electronic cash system.
Patsakis, C., Politou, E., Alepis, E., and Hernandez-Castro, J. (2024). Cashing out crypto: state of practice in ransom payments. International Journal of Information Security, 23:699–712.
Shojaeenasab, A., Motamed, A. P., and Bahrak, B. (2022). Mixing detection on bitcoin transactions using statistical patterns.
Tang, Y., Xu, C., Zhang, C., Wu, Y., and Zhu, L. (2022a). Analysis of Address Linkability in Tornado Cash on Ethereum, pages 39–50.
Tang, Y., Xu, C., Zhang, C., Wu, Y., and Zhu, L. (2022b). Analysis of address linkability in tornado cash on ethereum. In Communications in Computer and Information Science, volume 1506 CCIS, pages 39–50. Springer Science and Business Media Deutschland GmbH.
Team, C. (2023). 2023 crypto crime trends: Illicit cryptocurrency volumes reach all-time highs amid surge in sanctions designations and hacking-chainalysis. Chainalysis Crime Report, pages 1–8.
Team, T. (2021). Typhoon.network documentation. [link].
Tironsakkul, T., Maarek, M., Eross, A., and Just, M. (2020). Tracking mixed bitcoins.
Victor, F. and Weintraud, A. M. (2021). Detecting and quantifying wash trading on decentralized cryptocurrency exchanges. In The Web Conference 2021 - Proceedings of the World Wide Web Conference, WWW 2021, pages 23–32. Association for Computing Machinery, Inc.
Wang, Z., Chaliasos, S., Qin, K., Zhou, L., Gao, L., Berrang, P., Livshits, B., and Gervais, A. (2023a). On how zero-knowledge proof blockchain mixers improve, and worsen user privacy. In Proceedings of the ACM Web Conference 2023, WWW ’23, page 2022–2032, New York, NY, USA. Association for Computing Machinery.
Wang, Z., Chaliasos, S., Qin, K., Zhou, L., Gao, L., Berrang, P., Livshits, B., and Gervais, A. (2023b). On how zero-knowledge proof blockchain mixers improve, and worsen user privacy. In ACM Web Conference 2023 - Proceedings of the World Wide Web Conference, WWW 2023, pages 2022–2032. Association for Computing Machinery, Inc.
Wood, G. et al. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151(2014):1–32.
Xu, C., Xiong, R., Shen, X., Zhu, L., and Zhang, X. (2023). How to find a bitcoin mixer: A dual ensemble model for bitcoin mixing service detection. IEEE Internet of Things Journal, 10:17220–17230.
Youn, M., Chin, K., and Omote, K. (2023a). Empirical analysis of cryptocurrency mixer: Tornado cash. In 2023 Congress in Computer Science, Computer Engineering, Applied Computing (CSCE), pages 2324–2331.
Youn, M., Chin, K., and Omote, K. (2023b). Empirical analysis of cryptocurrency mixer: Tornado cash. In Proceedings - 2023 Congress in Computer Science, Computer Engineering, and Applied Computing, CSCE 2023, pages 2324–2331. Institute of Electrical and Electronics Engineers Inc.
Ziegeldorf, J. H., Grossmann, F., Henze, M., Inden, N., and Wehrle, K. (2015). Coinparty: Secure multi-party mixing of bitcoins. In Proceedings of the 5th ACM Conference on Data and Application Security and Privacy, CODASPY ’15, page 75–86, New York, NY, USA. Association for Computing Machinery.
Zola, F., Medina, J. A., Venturi, A., and Orduna, R. (2025). Topological analysis of mixer activities in the bitcoin network.
Published
2025-09-01
How to Cite
LEALE, Pedro; SENDIN, Ivan da Silva.
A Proposed Algorithm for Detecting Mixers in Ethereum. In: WORKSHOP ON SCIENTIFIC INITIATION AND UNDERGRADUATE ONGOING WORKS - BRAZILIAN SYMPOSIUM ON CYBERSECURITY (SBSEG), 25. , 2025, Foz do Iguaçu/PR.
Anais [...].
Porto Alegre: Sociedade Brasileira de Computação,
2025
.
p. 331-337.
DOI: https://doi.org/10.5753/sbseg_estendido.2025.10916.
