Authentication by speech at a machine

A method, comprising:

• providing, for display on a front-end device, a plurality of images, wherein each image, of the plurality of images, indicates a corresponding integer of integers zero through nine;
• receiving audio data that includes a sequence of words that describe a subset of the plurality of images to indicate a first sequence of numbers corresponding to a subset of the integers zero through nine;
• and
• authenticating a user based on the first sequence of numbers.

A non-transitory computer-readable medium storing a set of instructions, comprising:

• one or more instructions that, when executed by one or more processors of a device, cause the device to:
• provide, for display, a plurality of images corresponding to integers zero through nine, wherein each image, of the plurality of images, has a property that indicates a corresponding integer, of the integers zero through nine, for the image;
• receive audio data that includes a sequence of words that describe a subset of the plurality of images to indicate a first sequence of numbers corresponding to a subset of the integers zero through nine;
• and
• authenticate a user based on the first sequence of numbers.