Security Evaluation of Block-based Image Encryption for Vision Transformer against Jigsaw Puzzle Solver Attack

TL;DR

This paper assesses the security of block-based image encryption methods used in vision transformers by testing their resilience against jigsaw puzzle solver attacks, revealing vulnerabilities in current schemes.

Contribution

It provides the first evaluation of the security of block-based image encryption for vision transformers using jigsaw puzzle solver attacks.

Findings

Encrypted images are vulnerable to jigsaw puzzle solver attacks.

Block scrambling-based encryption schemes show limited resistance.

Security evaluation methodology for encrypted vision transformer images.

Abstract

The aim of this paper is to evaluate the security of a block-based image encryption for the vision transformer against jigsaw puzzle solver attacks. The vision transformer, a model for image classification based on the transformer architecture, is carried out by dividing an image into a grid of square patches. Some encryption schemes for the vision transformer have been proposed by applying block-based image encryption such as block scrambling and rotating to patches of the image. On the other hand, the security of encryption scheme for the vision transformer has never evaluated. In this paper, jigsaw puzzle solver attacks are utilized to evaluate the security of encrypted images by regarding the divided patches as pieces of a jigsaw puzzle. In experiments, an image is resized and divided into patches to apply block scrambling-based image encryption, and then the security of encrypted images for the vision transformer against jigsaw puzzle solver attacks is evaluated.