skip to main content
Caltech
Information Management Systems and Services
IMSS  /  Services  /  Information Security  /  Duo MFA  /  Authentication Methods  /  YubiKey Security Key

How to use YubiKey Security Key

A YubiKey is a hardware device that can be used as a second-factor option with Duo.

Note: some YubiKey devices can function as a passcode generator as well as a Security Key. Others can only function as a security key. This document describes using a YubiKey as a security key. Please also see "How to use YubiKey passcode" and "What is the difference between YubiKey Passcode and YubiKey Security Key"?

How YubiKey security key works

A YubiKey security key can only be used with browser-based applications. After you log in with your username and password, Duo prompts you to "Use your security key". Tap the button on your YubiKey device.

How to set up YubiKey security key

  1. Navigate to the Duo Device Management Portal.
  2. Select "Add a device" then select "Security key" and "Continue"
  3. Follow the prompts on the screen to set up the YubiKey security key. If you are prompted to save a security using a mobile device, select the option "Use a different phone, tablet, or security key".
  4. When prompted to "Insert and touch your security key", make sure the YubiKey device is inserted into your computer, then tap the button on the key.

How to authenticate using YubiKey security key

  1. Log in to a Duo-protected service using your username and password
  2. Duo will prompt you to "Use your security key", or "Insert your security key and touch it". If you do not see the this prompt, Duo may have defaulted to a different authentication method. Click "Other options" and then "Security key" to manually select this option. If you do not see "Security key" in the list of options, you have not set up this method yet. Refer to the instructions above.
  3. Insert the YubiKey into a USB port in your computer if it is not connected already. When prompted to "Use your security key", tap the button on the key.