Integrity of Stored Public Key
Original Publication Date: 1986-May-01
Included in the Prior Art Database: 2005-Mar-09
This article describes a method for protecting the integrity of a public key 10 stored in a terminal 12 on the basis of a secret key 14 stored in that terminal. A terminal with only a public key, but no secret key, cannot be tested to ensure its integrity. The obvious attack against a terminal with only an installed public key is to replace that public key with a public key selected by the adversary. The adversary thus selects a public key for which the corresponding secret key is known, thereby allowing data encrypted with that public key to be decrypted by the adversary using the known secret key. This basic attack can take several forms. The diagram illustrates a network in which the terminal device 12 is connected to a key distribution center (KDC) 16.