:original_name: waf_01_0024.html

.. _waf_01_0024:

Handling False Alarms
=====================

If you confirm that an attack event on the **Events** page is a false alarm, you can handle the event as false alarm by ignoring the URL and rule ID in basic web protection, or by deleting or disabling the corresponding protection rule you configured. After an attack event is handled as a false alarm, the event will not be displayed on the **Events** page anymore. You will no longer receive any alarm notifications about the event.

WAF detects attacks by using built-in basic web protection rules, built-in features in anti-crawler protection, and custom rules you configured (such as CC attack protection, precise access protection, blacklist, whitelist, and geolocation access control rules). WAF will respond to detected attacks based on the protective actions (such as **Block** and **Log only**) defined in the rules and display attack events on the **Events** page.

Prerequisites
-------------

There is at least one false alarm event in the event list.

Constraints
-----------

-  Only attack events blocked or recorded by preconfigured basic web protection rules and features in anti-crawler protection can be handled as false alarms.
-  For events generated based on custom rules (such as a CC attack protection rule, precise protection rule, blacklist rule, whitelist rule, or geolocation access control rule), they cannot be handled as false alarms. To ignore such an event, delete or disable the custom rule hit by the event.
-  An attack event can only be handled as a false alarm once.

Application Scenarios
---------------------

Sometimes normal service requests may be blocked by WAF. For example, suppose you deploy a web application on an ECS and then add the public domain name associated with that application to WAF. If you enable basic web protection for that application, WAF may block the access requests that match the basic web protection rules. As a result, the website cannot be accessed through its domain name. However, the website can still be accessed through the IP address. In this case, you can handle the false alarms to allow normal access requests to the application.

Impact on the System
--------------------

The attack event will not be displayed on the **Events** page. You will no longer receive any alarm notifications about the event.

Procedure
---------

#. Log in to the management console.

#. Click |image1| in the upper left corner of the management console and select a region or project.

#. Click |image2| in the upper left corner and choose **Web Application Firewall (Dedicated)** under **Security**.

#. In the navigation pane on the left, choose **Events**.

#. Select the **Search** tab. Select a website from the **All protected websites** drop-down list. Then, select **Yesterday**, **Today**, **Past 3 days**, **Past 7 days**, **Past 30 days**, or a custom time range. :ref:`Table 1 <waf_01_0024__table146358613417>` and :ref:`Table 2 <waf_01_0024__table135241210519>` describe parameters.


   .. figure:: /_static/images/en-us_image_0000001395650509.png
      :alt: **Figure 1** Viewing protection events

      **Figure 1** Viewing protection events

   .. _waf_01_0024__table146358613417:

   .. table:: **Table 1** Event parameters

      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
      | Parameter                         | Description                                                                                                                                                                                       |
      +===================================+===================================================================================================================================================================================================+
      | Event Type                        | Type of attack.                                                                                                                                                                                   |
      |                                   |                                                                                                                                                                                                   |
      |                                   | By default, **All** is selected. You can view logs of all attack types or select an attack type to view corresponding attack logs.                                                                |
      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
      | Protective Action                 | The options are **Block**, **Log only**, and **Verification code**.                                                                                                                               |
      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
      | Source IP Address                 | Public IP address of the web visitor/attacker                                                                                                                                                     |
      |                                   |                                                                                                                                                                                                   |
      |                                   | By default, **All** is selected. You can view logs of all attack source IP addresses, select an attack source IP address, or enter an attack source IP address to view corresponding attack logs. |
      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
      | URL                               | Attacked URL                                                                                                                                                                                      |
      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
      | Event ID                          | ID of the event                                                                                                                                                                                   |
      +-----------------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

   .. _waf_01_0024__table135241210519:

   .. table:: **Table 2** Parameters in the event list

      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Parameter             | Description                                                                                                                                                               | Example Value         |
      +=======================+===========================================================================================================================================================================+=======================+
      | Time                  | When the attack occurred                                                                                                                                                  | 2021/02/04 13:20:04   |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Source IP Address     | Public IP address of the web visitor/attacker                                                                                                                             | None                  |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Geolocation           | Location where the IP address of the attack originates from                                                                                                               | ``-``                 |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Domain Name           | Attacked domain name                                                                                                                                                      | www.example.com       |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | URL                   | Attacked URL                                                                                                                                                              | /admin                |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Malicious Load        | The location or part of the attack that causes damage or the number of times that the URL was accessed.                                                                   | id=1 and 1='1         |
      |                       |                                                                                                                                                                           |                       |
      |                       | .. note::                                                                                                                                                                 |                       |
      |                       |                                                                                                                                                                           |                       |
      |                       |    -  In a CC attack, the malicious load indicates the number of times that the URL was accessed.                                                                         |                       |
      |                       |    -  For blacklist protection events, the malicious load is left blank.                                                                                                  |                       |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Event Type            | Type of attack                                                                                                                                                            | SQL injection         |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Protective Action     | Protective actions configured in the rule. The options are **Block**, **Log only**, and **Verification code**.                                                            | Block                 |
      |                       |                                                                                                                                                                           |                       |
      |                       | .. note::                                                                                                                                                                 |                       |
      |                       |                                                                                                                                                                           |                       |
      |                       |    If an access request matches a web tamper protection rule, information leakage prevention rule, or data masking rule, the protective action is marked as **Mismatch**. |                       |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+
      | Status Code           | HTTP status code returned on the block page.                                                                                                                              | 418                   |
      +-----------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------+

   .. note::

      To view event details, click **Details** in the **Operation** column of the event list.

#. After you confirm that an event is a false alarm, click **Handle False Alarm** in the **Operation** column of the row and add a false alarm masking rule. :ref:`Table 3 <waf_01_0024__table1623195815237>` describes parameters.


   .. figure:: /_static/images/en-us_image_0000001327191500.png
      :alt: **Figure 2** Handling a false alarm

      **Figure 2** Handling a false alarm

   .. _waf_01_0024__table1623195815237:

   .. table:: **Table 3** Parameters

      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Parameter               | Description                                                                                                                                                                                                                                                                                                                                                               | Example Value                              |
      +=========================+===========================================================================================================================================================================================================================================================================================================================================================================+============================================+
      | Scope                   | -  **All domain names**: By default, this rule will be used to all domain names that are protected by the current policy.                                                                                                                                                                                                                                                 | Specified domain names                     |
      |                         | -  **Specified domain names**: This rule will be used to the specified domain names that match the wildcard domain name being protected by the current policy.                                                                                                                                                                                                            |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Domain Name             | This parameter is mandatory when you select **Specified domain names** for **Scope**.                                                                                                                                                                                                                                                                                     | www.example.com                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | Enter a single domain name that matches the wildcard domain name being protected by the current policy.                                                                                                                                                                                                                                                                   |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Condition List          | Click **Add** to add conditions. At least one condition needs to be added. You can add up to 30 conditions to a protection rule. If more than one condition is added, all of the conditions must be met for the rule to be applied. A condition includes the following parameters:                                                                                        | Path, Include, /product                    |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | Parameters for configuring a condition are described as follows:                                                                                                                                                                                                                                                                                                          |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | -  Field                                                                                                                                                                                                                                                                                                                                                                  |                                            |
      |                         | -  **Subfield**: Configure this field only when **Params**, **Cookie**, or **Header** is selected for **Field**.                                                                                                                                                                                                                                                          |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         |    .. important::                                                                                                                                                                                                                                                                                                                                                         |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         |       NOTICE:                                                                                                                                                                                                                                                                                                                                                             |                                            |
      |                         |       The length of a subfield cannot exceed 2,048 bytes. Only digits, letters, underscores (_), and hyphens (-) are allowed.                                                                                                                                                                                                                                             |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | -  **Logic**: Select a logical relationship from the drop-down list.                                                                                                                                                                                                                                                                                                      |                                            |
      |                         | -  **Content**: Enter or select the content that matches the condition.                                                                                                                                                                                                                                                                                                   |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Ignore WAF Protection   | -  **All protection**: All WAF rules do not take effect, and WAF allows all request traffic to the domain names in the rule.                                                                                                                                                                                                                                              | Basic Web Protection                       |
      |                         | -  **Basic Web Protection**: You can ignore basic web protection by rule ID, attack type, or all built-in rules. For example, if XSS check is not required for a URL, you can whitelist XSS rule.                                                                                                                                                                         |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Ignored Protection Type | If you select **Basic web protection** for **Ignored Protection Type**, specify the following parameters:                                                                                                                                                                                                                                                                 | Attack type                                |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | -  **ID**: Configure the rule by event ID.                                                                                                                                                                                                                                                                                                                                |                                            |
      |                         | -  **Attack type**: Configure the rule by attack type, such as XSS and SQL injection. One type contains one or more rule IDs.                                                                                                                                                                                                                                             |                                            |
      |                         | -  **All built-in rules**: all checks enabled in :ref:`Basic Web Protection <waf_01_0008>`.                                                                                                                                                                                                                                                                               |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | ID                      | This parameter is mandatory when you select **ID** for **Ignored Protection Type**.                                                                                                                                                                                                                                                                                       | 041046                                     |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | ID of an attack event on the **Events** page. If the event type is **Custom**, it has no event ID. Click **Handle False Alarm** in the row containing the attack event to obtain the ID. You are advised to configure global protection whitelist (formerly false alarm masking) rules on the **Events** page by referring to :ref:`Handling False Alarms <waf_01_0024>`. |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Attack type             | This parameter is mandatory when you select **Attack type** for **Ignored Protection Type**.                                                                                                                                                                                                                                                                              | SQL injection                              |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | Select an attack type from the drop-down list box.                                                                                                                                                                                                                                                                                                                        |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | WAF can defend against XSS attacks, web shells, SQL injection attacks, malicious crawlers, remote file inclusions, local file inclusions, command injection attacks, and other attacks.                                                                                                                                                                                   |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Rule Description        | A brief description of the rule. This parameter is optional.                                                                                                                                                                                                                                                                                                              | SQL injection attacks are not intercepted. |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+
      | Advanced Settings       | To ignore attacks of a specific field, specify the field in the **Advanced Settings** area. After you add the rule, WAF will stop blocking attack events of the specified field.                                                                                                                                                                                          | Params                                     |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | Select a target field from the first drop-down list box on the left. The following fields are supported: **Params**, **Cookie**, **Header**, **Body**, and **Multipart**.                                                                                                                                                                                                 | All                                        |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | -  If you select **Params**, **Cookie**, or **Header**, you can select **All** or **Specified field** to configure a subfield.                                                                                                                                                                                                                                            |                                            |
      |                         | -  If you select **Body** or **Multipart**, you can select **All**.                                                                                                                                                                                                                                                                                                       |                                            |
      |                         | -  If you select **Cookie**, the **Domain Name** and **Path** can be empty.                                                                                                                                                                                                                                                                                               |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         | .. note::                                                                                                                                                                                                                                                                                                                                                                 |                                            |
      |                         |                                                                                                                                                                                                                                                                                                                                                                           |                                            |
      |                         |    If **All** is selected, WAF will not block all attack events of the selected field.                                                                                                                                                                                                                                                                                    |                                            |
      +-------------------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------+

#. Click **OK**.

Verification
------------

A false alarm will be deleted within about a minute after the handling configuration is done. It will no longer be displayed in the attack event details list. You can refresh the browser cache and request the page for which the false alarm masking rule is configured to check whether the configuration takes effect.

Other Operations
----------------

If an event is handled as a false alarm, the rule hit will be added to the global protection whitelist (formerly false alarm masking) rule list. You can go to the **Policies** page and then switch to the **Global Protection Whitelist (Formerly False Alarm Masking)** page to manage the rule, including querying, disabling, deleting, and modifying the rule. For more details, see :ref:`Configuring a Global Protection Whitelist (Formerly False Alarm Masking) Rule <waf_01_0016>`.

.. |image1| image:: /_static/images/en-us_image_0000001493990116.jpg
.. |image2| image:: /_static/images/en-us_image_0000001288106950.png