Abstract: Techniques are disclosed relating to using a randomized private input interface to secure passcode information. In some embodiments, a mobile device receives configuration information for user input of a passcode to another device. In some embodiments, the configuration information specifies a pseudo-random relationship of input values to input actions recognized by the other device. In some embodiments, a private interface is displayed based on the configuration information, where the private interface is visible to a user of the mobile device and not to others. In various embodiments, the disclosed techniques may reduce the ability of other nearby individuals to determine information entered by the user.

Abstract: A system includes a server computer system that may receive an authorization request from a first user for a transaction that includes a request for resources from a user account. The authorization request may include an identification value for a second, different user that has authorization authority for the user account. The server computer system may send transaction details to an authentication server that may make authorization determinations for the transaction based on a passcode and a reference value. The reference value may be generated based on the transaction details. The system may also receive confirmation data from the authentication server. This confirmation data may be generated by the authentication server based on the transaction details. The system may further send, to the first user, the passcode for communication to the second user, and may receive an indication whether the second user has authorized the transaction.