Two Factor

Description

The Two-Factor plugin adds an extra layer of security to your WordPress login by requiring users to provide a second form of authentication in addition to their password. This helps protect against unauthorized access even if passwords are compromised.

Setup Instructions

Important: Each user must individually configure their two-factor authentication settings. There are no site-wide settings for this plugin.

For Individual Users

1. Navigate to your profile: Go to “Users” → “Your Profile” in the WordPress admin
2. Find Two-Factor Options: Scroll down to the “Two-Factor Options” section
3. Choose your methods: Enable one or more authentication providers (noting a site admin may have hidden one or more so what is available could vary):
   • Authenticator App (TOTP) – Use apps like Google Authenticator, Authy, or 1Password
   • Email Codes – Receive one-time codes via email
   • FIDO U2F Security Keys – Use physical security keys (requires HTTPS)
   • Backup Codes – Generate one-time backup codes for emergencies
   • Dummy Method – For testing purposes only (requires WP_DEBUG)
4. Configure each method: Follow the setup instructions for each enabled provider
5. Set primary method: Choose which method to use as your default authentication
6. Save changes: Click “Update Profile” to save your settings

For Site Administrators

• No global settings: This plugin operates on a per-user basis only. For more, see GH#249.
• User management: Administrators can configure 2FA for other users by editing their profiles
• Security recommendations: Encourage users to enable backup methods to prevent account lockouts

Available Authentication Methods

Authenticator App (TOTP) – Recommended

• Security: High – Time-based one-time passwords
• Setup: Scan QR code with authenticator app
• Compatibility: Works with Google Authenticator, Authy, 1Password, and other TOTP apps
• Best for: Most users, provides excellent security with good usability

Backup Codes – Recommended

• Security: Medium – One-time use codes
• Setup: Generate 10 backup codes for emergency access
• Compatibility: Works everywhere, no special hardware needed
• Best for: Emergency access when other methods are unavailable

Email Codes

• Security: Medium – One-time codes sent via email
• Setup: Automatic – uses your WordPress email address
• Compatibility: Works with any email-capable device
• Best for: Users who prefer email-based authentication

FIDO U2F Security Keys

• Security: High – Hardware-based authentication
• Setup: Register physical security keys (USB, NFC, or Bluetooth)
• Requirements: HTTPS connection required, compatible browser needed
• Browser Support: Chrome, Firefox, Edge (varies by key type)
• Best for: Users with security keys who want maximum security

Dummy Method

• Security: None – Always succeeds
• Setup: Only available when WP_DEBUG is enabled
• Purpose: Testing and development only
• Best for: Developers testing the plugin

Important Notes

HTTPS Requirement

• FIDO U2F Security Keys require an HTTPS connection to function
• Other methods work on both HTTP and HTTPS sites

Browser Compatibility

• FIDO U2F requires a compatible browser and may not work on all devices
• TOTP and email methods work on all devices and browsers

Account Recovery

• Always enable backup codes to prevent being locked out of your account
• If you lose access to all authentication methods, contact your site administrator

Security Best Practices

• Use multiple authentication methods when possible
• Keep backup codes in a secure location
• Regularly review and update your authentication settings

For more information about two-factor authentication in WordPress, see the WordPress Advanced Administration Security Guide.

For more history, see this post.

Actions & Filters

Here is a list of action and filter hooks provided by the plugin:

• two_factor_providers filter overrides the available two-factor providers such as email and time-based one-time passwords. Array values are PHP classnames of the two-factor providers.
• two_factor_providers_for_user filter overrides the available two-factor providers for a specific user. Array values are instances of provider classes and the user object WP_User is available as the second argument.
• two_factor_enabled_providers_for_user filter overrides the list of two-factor providers enabled for a user. First argument is an array of enabled provider classnames as values, the second argument is the user ID.
• two_factor_user_authenticated action which receives the logged in WP_User object as the first argument for determining the logged in user right after the authentication workflow.
• two_factor_user_api_login_enable filter restricts authentication for REST API and XML-RPC to application passwords only. Provides the user ID as the second argument.
• two_factor_email_token_ttl filter overrides the time interval in seconds that an email token is considered after generation. Accepts the time in seconds as the first argument and the ID of the WP_User object being authenticated.
• two_factor_email_token_length filter overrides the default 8 character count for email tokens.
• two_factor_backup_code_length filter overrides the default 8 character count for backup codes. Provides the WP_User of the associated user as the second argument.
• two_factor_rest_api_can_edit_user filter overrides whether a user’s Two-Factor settings can be edited via the REST API. First argument is the current $can_edit boolean, the second argument is the user ID.
• two_factor_before_authentication_prompt action which receives the provider object and fires prior to the prompt shown on the authentication input form.
• two_factor_after_authentication_prompt action which receives the provider object and fires after the prompt shown on the authentication input form.
• two_factor_after_authentication_inputaction which receives the provider object and fires after the input shown on the authentication input form (if form contains no input, action fires immediately after two_factor_after_authentication_prompt).