Advanced Threat Detection

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This feature is only available in the Enterprise plan. Please visit our pricing page to learn more.


Available since 1.30.0

Flagging and responding to suspicious behavior is a part of any cybersecurity product. Advanced Threat Detection, a feature that brings best-practice functionality to help you deal with bizarre, possibly malicious behavior around logins, registrations, user creation, and user updates.

Advanced Threat Detection can be enabled when the user creates a license or updates an existing license.

This feature also requires increased RAM on the servers running the FusionAuth application, as documented in the System Requirements.

Advanced Threat Detection includes:

Each is configurable on a tenant by tenant basis. You can do so via the Tenant API or by navigating to Tenants -> My Tenant -> Security .

Here’s a brief video covering some aspects of Advanced Threat Detection:

Customizable Rate Limiting

These are per user rate limits for the following user actions:

  • Failed login
  • Forgot password
  • Send or resend email verification
  • Passwordless/magic link login
  • Send or resend registration verification
  • Send two-factor code
The rate limiting configuration screen.

You can enable or disable each of these and control the number of allowed attempts within a window before an action will be rate limited. When an action is rate limited, it will not succeed.

When configured, rate limiting applies whether you are using the hosted login pages or the APIs.

If you need to lock an account after a number of failed logins, consider user account locking. Using the account lockout feature rather than rate limiting offers additional flexibility in the duration. You can also send emails or fire webhooks when a user’s account is locked.


CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart, and can provide additional security. FusionAuth will require a CAPTCHA in certain circumstances such as when a device has never been seen before.

There are a variety of paid and free CAPTCHAs supported, including Google ReCaptcha and HCaptcha.

Location Aware Security

FusionAuth has location information for requests and uses it in a variety of ways to secure user accounts. These are all configurable and controllable by developers integrating FusionAuth into their applications.

Some location aware features include:

  • Inside of every Forgot/Reset Password email sent to a user, the geographic location of where the password reset request was made is displayed. The recipient can determine if the location of the requester seems suspicious.
  • Flag suspicious login events and notify the user of a new login with the approximate location. A webhook is also sent.
  • Calculates “impossible travel” to see if a user could realistically log in at different locations around the globe in a reasonable time frame.
  • When a login request occurs from an unexpected IP address, a user receives an email to notify them of a new login with an approximate location of the IP address.


For security purposes, you may want to lock down an application or API key to a certain IP address or range of IP addresses.

With Advanced Threat Detection, you can do this. Create an IP address access control list (IP ACL):

The IP access control list configuration screen.

Then apply it to an application (if using the hosted login pages). This will prevent a user from being able to even access an application login page if they are not in the IP address range. If you have internal applications or applications to which access should otherwise be limited, this feature can help lock those applications down.

Applying an IP ACL to an application.

You can also lock down an API key to a given range with an IP ACL. This is useful if you are managing your FusionAuth configuration via a CI/CD system. You can create an API key to modify configurations, but limit that key to the IP address range of your CI/CD system, increasing security and lowering the risk of the API key being used incorrectly.

Applying an IP ACL to an API key.

Registration Domain Blocking

If you enable self service registration, users can provide any email address they like. But you may have email domains that have elevated privileges, like your domain. There may be email addresses for which you want to block registration, like consumer addresses if your application is aimed at business users.

In either of these cases, you can block one or more domains from the registration process using Advanced Threat Detection.

Blocking consumer facing domains from registering.

Webhook Events

There are a number of security related events that your SIEM or other analytics systems may want to ingest, such as when MFA has been disabled for a user or when a user has requested a password reset.

Here’s the full list of Advanced Threat Detection webhooks:

Security Emails

Emails can be sent to the user when certain security-related events occur. You can add your own email templates. There is a sample “Threat Detected” email template which documents available variables. Security related emails may be localized like any other email template.

Here are the security events for which you can send emails:

  • Login Id duplicate on create - someone tried to create a user which collided with an existing username or password
  • Login Id duplicate on update - someone tried to update a user to have a loginId which collided with an existing username or password
  • Login with new device - someone logged in with a device not previously used
  • Suspicious login - the login has been flagged by FusionAuth as suspicious
  • Password reset success - a successful ‘forgot password’ flow for the user has completed
  • Password update - a user’s password has been updated by any means
  • Two-factor method added - an MFA method was added to a user’s account
  • Two-factor method removed - an MFA method was removed to a user’s account

You can set these up by navigating to Tenant -> Your Tenant -> Email -> Template Settings.

List of email templates.