Citrix Application Delivery Management service

WAF learning engine

Citrix Web App Firewall (WAF) protects your web applications from malicious attacks such as SQL injection and cross-site scripting. To prevent data breaches and provide the right security protection, you must monitor your traffic for threats and real-time actionable data on attacks. Sometimes, the attacks reported might be false-positive and those need to be provided as an exception.

The Learning engine on Citrix ADM is a repetitive pattern filter that enables WAF to learn the behavior (the normal activities) of your web applications. Based on monitoring, the engine generates a list of suggested rules or exceptions for each security check applied on the HTTP traffic.

It is much easier to deploy relaxation rules using the Learning engine than manually deploy it as necessary relaxations.

The following image explains the high-level information on how the WAF learning in Citrix ADM works:

WAF intro

1 – Citrix ADC instances with its WAF profiles

2 – Configure a learning profile in Citrix ADM, add the WAF profiles, and select to auto deploy or manually deploy the relaxation rules

3 – Administrator can validate the relaxation rules in Citrix ADM and decide to deploy or skip

Get started

To deploy the learning feature, you must:

  • Enable the centralized learning in the ADC instance. Run the following command in the ADC instance:

    set appfw settings -centralizedLearning ON

  • Configure a Web App Firewall profile (set of security settings) on your Citrix ADC appliance. For more information, see Creating Web App Firewall profiles.

After you enable the centralized learning and configure the WAF profile, Citrix ADM generates a list of exceptions (relaxations) for the configured security check. As an administrator, you can review the list of exceptions in Citrix ADM and decide to deploy or skip.

Using the WAF learning feature in Citrix ADM, you can:

  • Configure a learning profile with the following security checks

    • Start URL

    • Cookie Consistency

    • Credit Card


      For the credit card security check, you must configure the doSecureCreditCardLogging in Citrix ADC instance and ensure the setting is OFF.

    • Content Type

    • Form Field Consistency

    • Field Formats

    • CSRF Form Tagging

    • HTML Cross-Site Scripting

    • HTML SQL Injection


      For the HTML SQL Injection check, you must configure set -sqlinjectionTransformSpecialChars ON and set -sqlinjectiontype sqlspclcharorkeywordsin Citrix ADC instance.

    • HTML Command Injection


      Supported only in ADC instance 13.0-72.12 or later.

  • Check the relaxation rules in Citrix ADM and decide to take necessary action (deploy or skip)

  • Get the notifications through email, slack, and ServiceNow

  • Use the Action Summary page to view relaxation details

To use the WAF learning in Citrix ADM:

  1. Configure the learning profile

  2. See the relaxation rules

  3. Use the WAF learning Action Summary page

WAF learning engine