Adding the ACFP managed rule group to your web ACL - AWS WAF, AWS Firewall Manager, and AWS Shield Advanced

Adding the ACFP managed rule group to your web ACL

This section explains how to add and configure the AWSManagedRulesACFPRuleSet rule group.

To configure the ACFP managed rule group to recognize account creation fraud activities in your web traffic, you provide information about how clients access your registration page and send account creation requests to your application. For protected Amazon CloudFront distributions, you also provide information about how your application responds to account creation requests. This configuration is in addition to the normal configuration for a managed rule group.

For the rule group description and rules listing, see AWS WAF Fraud Control account creation fraud prevention (ACFP) rule group.

Note

The ACFP stolen credentials database only contains usernames in email format.

This guidance is intended for users who know generally how to create and manage AWS WAF web ACLs, rules, and rule groups. Those topics are covered in prior sections of this guide. For basic information about how to add a managed rule group to your web ACL, see Adding a managed rule group to a web ACL through the console.

Follow best practices

Use the ACFP rule group in accordance with the best practices at Best practices for intelligent threat mitigation in AWS WAF.

To use the AWSManagedRulesACFPRuleSet rule group in your web ACL

  1. Add the AWS managed rule group, AWSManagedRulesACFPRuleSet to your web ACL, and Edit the rule group settings before saving.

    Note

    You are charged additional fees when you use this managed rule group. For more information, see AWS WAF Pricing.

  2. In the Rule group configuration pane, provide the information that the ACFP rule group uses to inspect account creation requests.

    1. For Use regular expression in paths, toggle this on if you want AWS WAF to perform regular expression matching for your registration and account creation page path specifications.

      AWS WAF supports the pattern syntax used by the PCRE library libpcre with some exceptions. The library is documented at PCRE - Perl Compatible Regular Expressions. For information about AWS WAF support, see Supported regular expression syntax in AWS WAF.

    2. For Registration page path, provide the path of the registration page endpoint for your application. This page must accept GET text/html requests. The rule group inspects only HTTP GET text/html requests to your specified registration page endpoint.

      Note

      Matching for endpoints is case insensitive. Regex specifications must not contain the flag (?-i), which disables case insensitive matching. String specifications must start with a forward slash /.

      For example, for the URL https://example.com/web/registration, you could provide the string path specification /web/registration. Registration page paths that start with the path that you provide are considered a match. For example /web/registration matches the registration paths /web/registration, /web/registration/, /web/registrationPage, and /web/registration/thisPage, but doesn't match the path /home/web/registration or /website/registration.

      Note

      Ensure that your end users load the registration page before they submit an account creation request. This helps ensure that the account creation requests from the client include valid tokens.

    3. For Account creation path, provide the URI in your website that accepts completed new user details. This URI must accept POST requests.

      Note

      Matching for endpoints is case insensitive. Regex specifications must not contain the flag (?-i), which disables case insensitive matching. String specifications must start with a forward slash /.

      For example, for the URL https://example.com/web/newaccount, you could provide the string path specification /web/newaccount. Account creation paths that start with the path that you provide are considered a match. For example /web/newaccount matches the account creation paths /web/newaccount, /web/newaccount/, /web/newaccountPage, and /web/newaccount/thisPage, but doesn't match the path /home/web/newaccount or /website/newaccount.

    4. For Request inspection, specify how your application accepts account creation attempts by providing the request payload type and the names of the fields within the request body where the username, password, and other account creation details are provided.

      Note

      For the primary address and phone number fields, provide the fields in the order in which they appear in the request payload.

      Your specification of the field names depends on the payload type.

      • JSON payload type – Specify the field names in JSON pointer syntax. For information about the JSON Pointer syntax, see the Internet Engineering Task Force (IETF) documentation JavaScript Object Notation (JSON) Pointer.

        For example, for the following example JSON payload, the username field specification is /signupform/username and the primary address field specifications are /signupform/addrp1, /signupform/addrp2, and /signupform/addrp3.

        {
    "signupform": {
        "username": "THE_USERNAME",
        "password": "THE_PASSWORD",
        "addrp1": "PRIMARY_ADDRESS_LINE_1",
        "addrp2": "PRIMARY_ADDRESS_LINE_2",
        "addrp3": "PRIMARY_ADDRESS_LINE_3",
        "phonepcode": "PRIMARY_PHONE_CODE",
        "phonepnumber": "PRIMARY_PHONE_NUMBER"
    }
}

      • FORM_ENCODED payload type – Use the HTML form names.

        For example, for an HTML form with user and password input elements named username1 and password1, the username field specification is username1 and the password field specification is password1.

    5. If you're protecting Amazon CloudFront distributions, then under Response inspection, specify how your application indicates success or failure in its responses to account creation attempts.

      Note

      ACFP response inspection is available only in web ACLs that protect CloudFront distributions.

      Specify a single component in the account creation response that you want ACFP to inspect. For the Body and JSON component types, AWS WAF can inspect the first 65,536 bytes (64 KB) of the component.

      Provide your inspection criteria for the component type, as indicated by the interface. You must provide both success and failure criteria to inspect for in the component.

      For example, say your application indicates the status of an account creation attempt in the status code of the response, and uses 200 OK for success and 401 Unauthorized or 403 Forbidden for failure. You would set the response inspection Component type to Status code, then in the Success text box enter 200 and in the Failure text box, enter 401 on the first line and 403 on the second.

      The ACFP rule group only counts responses that match your success or failure inspection criteria. The rule group rules act on clients while they have too high a success rate among the responses that are counted, in order to mitigate bulk account creation attempts. For accurate behavior by the rule group rules, be sure to provide complete information for both successful and failed account creation attempts.

      To see the rules that inspect account creation responses, look for VolumetricIPSuccessfulResponse and VolumetricSessionSuccessfulResponse in the rules listing at AWS WAF Fraud Control account creation fraud prevention (ACFP) rule group.

  3. Provide any additional configuration that you want for the rule group.

    You can further limit the scope of requests that the rule group inspects by adding a scope-down statement to the managed rule group statement. For example, you can inspect only requests with a specific query argument or cookie. The rule group will only inspect requests that match the criteria in your scope-down statement and that are sent to the account registration and account creation paths that you specified in the rule group configuration. For information about scope-down statements, see Using scope-down statements in AWS WAF.

  4. Save your changes to the web ACL.

Before you deploy your ACFP implementation for production traffic, test and tune it in a staging or testing environment until you are comfortable with the potential impact to your traffic. Then test and tune the rules in count mode with your production traffic before enabling them. See the section that follows for guidance.