On the Sensitivity to Errors in Homomorphic Computing: Single Transient Bit-flip Client-side Error Characterization

2026-08-11

AI Summary

This work addresses the vulnerability of the CKKS homomorphic encryption scheme to bit-level transient faults, which can lead to silent data corruption due to its lack of fault tolerance. The study presents the first systematic analysis of how single-bit flip errors propagate through CKKS computations, with a particular focus on the error-amplifying effect inherent in homomorphic multiplication. Through bit-level fault injection and error propagation modeling, the authors identify homomorphic multiplication as the critical bottleneck for error sensitivity and highlight the widespread absence of fault-tolerant mechanisms in current deployments. These findings provide a theoretical foundation and concrete directions for designing more robust privacy-preserving computing systems resilient to hardware-level faults.

Abstract

Homomorphic Encryption (HE) enables computation on encrypted data without decryption and is a key primitive for privacy-preserving computation in sensitive domains such as healthcare, finance, and government. Its security relies on noise injection, which introduces intrinsic error sensitivity and raises concerns about the fault tolerance of HE systems, as hardware- and software-induced faults can evade traditional detection mechanisms and lead to silent data corruption. In this work, we analyze the sensitivity of HE to bit-level faults, focusing on the CKKS (Cheon--Kim--Kim--Song) scheme widely used for approximate arithmetic in AI and machine learning workloads. We identify homomorphic multiplication as the most error-sensitive operation in practical HE pipelines and characterize how faults propagate and amplify through it, exposing a critical robustness vulnerability and motivating the need for more resilient HE deployments.

Problem

• Homomorphic Encryption
• Error Sensitivity
• Bit-flip Fault
• Fault Tolerance
• CKKS

Innovation

• Homomorphic Encryption
• CKKS scheme
• bit-flip error
• error sensitivity
• fault propagation