Cryptanalysis of efficient controlled semi-quantum secret sharing protocol with entangled state.

Area of Science:

• Quantum Cryptography
• Information Security

Background:

• Quantum secret sharing is crucial for secure key management and multiparty computation.
• Recent advancements include controlled semi-quantum secret sharing protocols using entangled states.

Purpose of the Study:

• To perform a cryptanalysis of an efficient controlled semi-quantum secret sharing protocol.
• To identify vulnerabilities and assess the protocol's security guarantees.

Main Methods:

• Cryptanalysis of the proposed protocol.
• Simulation of attack scenarios, including collusion and denial-of-service.

Main Results:

• The controller can collude with a single participant to recover the secret.
• An external adversary can inject undetected errors (false secrets) via denial-of-service attacks.

Conclusions:

• The protocol fails to meet essential security requirements.
• It does not ensure that unauthorized parties gain no information about the secret.
• The protocol's correctness cannot be guaranteed against the identified attacks.