Circular Security Counterexamples for Arbitrary Length Cycles from LWE

We describe a public key encryption that is IND-CPA secure under the Learning with Errors (LWE) assumption, but that is not circular secure for arbitrary length cycles. Previous separation results for cycle length greater than 2 require the use of indistinguishability obfuscation, which is not currently realizable under standard assumptions.

• Type: Journal
• Year: 2016
• Where: IACR
• Authors: Venkata Koppula, Brent Waters
• Keywords: Biometrics, IACR 2016