PETA: A Privacy-Enhanced Framework for Secure and Auditable Tax Analysis
DOI:
https://doi.org/10.65879/3070-5789.2025.01.08Keywords:
Fully homomorphic encryption, CKKS scheme, encrypted tax computationAbstract
The increasing global adoption of electronic tax systems inherently introduces significant privacy and security risks, primarily stemming from the reliance on cloud infrastructure for storing and processing highly sensitive financial data. Conventional digital tax platforms typically necessitate unrestricted access to taxpayers’ raw data, thereby rendering these systems acutely vulnerable to sophisticated cyberattacks, large-scale data breaches, and malicious insider threats. This exposure fundamentally compromises the confidentiality of personal financial records and demonstrably contributes to the erosion of public trust in governmental digital services. To address these challenges, we introduce a privacy-preserving framework specifically engineered for secure tax calculation. Our technical solution is founded on the strategic integration of Fully Homomorphic Encryption (FHE), specifically employing the Cheon-Kim-Kim-Song (CKKS) scheme. The CKKS scheme is uniquely suited to enabling approximate arithmetic on encrypted data, which facilitates the secure evaluation of complex, real-valued inputs, including income figures, allowable deductions, and financial risk metrics. We implemented an encrypted tax pipeline utilizing the CKKS scheme. This pipeline rigorously supports the necessary real-valued operations and ensures the secure computation of core tax outcomes, including the exact tax owed, potential refund amounts, and predictive fraud assessment, with inherent implications for compliant auditing and maintaining evidentiary integrity. Experimental results conclusively demonstrate that our proposed system maintains both high utility and accuracy in its calculations while simultaneously guaranteeing data confidentiality. This approach establishes a practical foundation for building secure, transparent, and trustworthy digital tax infrastructures.
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