Quantum digital signatures (QDS) provide information-theoretic security for data integrity, authenticity, and nonrepudiation by exploiting the laws of quantum mechanics. While existing QDS protocols have achieved significant efficiency improvements via one-time universal hashing, they rely on trusted quantum devices, requiring precise characterization and stable calibration of state preparation and measurement processes, which in practice cannot be fully guaranteed. Here, we propose a device-independent QDS protocol based on the violation of Bell inequalities and the entropy accumulation theorem, thereby ensuring information-theoretic security against general coherent attacks without assumptions on the internal functioning of the devices. We analyze the protocol performance under realistic noise and loss models and show that it is feasible with current experimental technology over multikilometer distances. Furthermore, by leveraging state-of-the-art single-photon sources, the achievable distance can be extended to several tens of kilometers. Our results establish device-independent QDS as a practical and scalable cryptographic primitive for secure applications in quantum networks with untrusted devices.

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• Quantum communication
• Quantum communication, protocols & technology
• Quantum protocols