| 摘要 |
A method includes engaging in authentication operations each involving apparent use of a legitimate authenticator. Values of one or more authenticator variables are received and stored, where the authenticator variable(s) normally change in a known authenticator-specific way during the authentication operations, such as being calculated from a monotonically increasing dynamic variable. A risk analysis function is applied to the stored values to generate a risk indicator signal indicating a level of risk that the clone authenticator is in use. The risk analysis function includes detection of an abnormal change of the authenticator variable(s), such as use of non-monotonic dynamic variable values. The risk indicator signal is output to an access controller that operates, based on the level of risk indicated by the risk indicator signal, to selectively inhibit an otherwise successful authentication operation involving apparent use of the legitimate authenticator. |
