Deniable Encryption
Deniable encryption lets the sender, under coercion, present a "fake key" that decrypts the ciphertext to an innocuous plaintext, while the real key decrypts it to the true plaintext; it is impossible to prove which one is genuine.
Purpose
It resists coerced key disclosure (rubber-hose cryptanalysis), protecting the sender’s communications under duress.
Mechanism
The construction makes one ciphertext C decrypt to the true plaintext M_real under key K_real and to an innocuous plaintext M_fake under key K_fake. Under coercion the sender hands over K_fake, and the existence of K_real cannot be proven.
Use cases
- Coercion-resistant communication
- High-privacy messaging
- Anonymous journalist sources