Recently, a non-interactive identity-based proxy re-encryption scheme was proposed for achieving CCA-security. In the paper, we show that the identity-based proxy re-encryption scheme is unfortunately vulnerable to a collusion attack. The collusion of a proxy and a malicious user enables two parties to derive other honest user's private key and thereby decrypt ciphertexts intended for the honest user.
- Collusion attack
- Identity-based proxy re-encryption
ASJC Scopus subject areas
- Theoretical Computer Science
- Signal Processing
- Information Systems
- Computer Science Applications