Verifiable-text attacks in cryptographic protocols

The author introduces a form of attack, a verifiable-test attack, in which an attacker obtains secret information, such as a password used in a protocol, without breaking the underlying cryptosystem. An investigation is made of the essence of a verifiable-text attack, and an algorithm for examining protocols and searching for vulnerabilities to such an attack is developed. Caution has to be exercised in certifying that a protocol is not vulnerable because a healthy protocol may become vulnerable when it interacts with another vulnerable or even healthy protocol