2023/06/27 by Marc Damie, Damie, Marc, Florian Hahn +3 · 2 citations
Computer Science · #Chaos-based Image/Signal Encryption #Cloud Data Security Solutions #Cryptography and Data Security #Cryptography and Security (cs.CR) #FOS: Computer and information sciences #Privacy-Preserving Technologies in Data
paper · pdf · doi:10.48550/arxiv.2306.15302
openalex publication_date 2023/06/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Cloud data storage solutions offer customers cost-effective and reduced data\nmanagement. While attractive, data security issues remain to be a core concern.\nTraditional encryption protects stored documents, but hinders simple\nfunctionalities such as keyword search. Therefore, searchable encryption\nschemes have been proposed to allow for the search on encrypted data. Efficient\nschemes leak at least the access pattern (the accessed documents per keyword\nsearch), which is known to be exploitable in query recovery attacks assuming\nthe attacker has a significant amount of background knowledge on the stored\ndocuments. Existing attacks can only achieve decent results with strong\nadversary models (e.g. at least 20% of previously known documents or require\nadditional knowledge such as on query frequencies) and they give no metric to\nevaluate the certainty of recovered queries. This hampers their practical\nutility and questions their relevance in the real-world.\n We propose a refined score attack which achieves query recovery rates of\naround 85% without requiring exact background knowledge on stored documents; a\ndistributionally similar, but otherwise different (i.e., non-indexed), dataset\nsuffices. The attack starts with very few known queries (around 10 known\nqueries in our experiments over different datasets of varying size) and then\niteratively recovers further queries with confidence scores by adding\npreviously recovered queries that had high confidence scores to the set of\nknown queries. Additional to high recovery rates, our approach yields\ninterpretable results in terms of confidence scores.\n