Exploring the Security Vulnerability in Frequency-Hiding Order-Preserving Encryption

Table 1

Comparison of the proposed method with other competing methods.

Method	Target	Attack	Applicability	Security	Assumptions
					Density	Auxiliary information
[24]	OPE	Sorting	Yes	IND-OCPA	High	Distribution of plaintexts
		Frequency-revealing			Low
[28]	FH-OPE	Frequency-revealing	No	IND-FA-OCPA	—	Distribution of nonuniform ciphertexts
						Insertion order of ciphertexts
Ours	FH-OPE	Frequency-revealing	Yes	IND-FA-OCPA	—	—

Applicability indicates whether the attack method can be applied across various encryption schemes. “Yes” signifies that the method is general and does not require knowledge of the specific encryption scheme, making it applicable to any OPE or FH-OPE system. “No” signifies that the method is scheme-specific, designed with full knowledge of a particular scheme’s details, and can only be applied to that specific system. In the security, IND-FA-OCPA denotes revised IND-FA-OCPA, addressing its original limitations. A high density means that all data in the plaintext space are encrypted. Conversely, low density implies that only a subset of the possible values in the plaintext space is encrypted. Auxiliary Information means the supplemental knowledge an adversary requires to successfully execute an attack.