Updated on 2024-04-12 GMT+08:00

Configuring a CC Attack Protection Rule

You can customize a CC attack protection rule to restrict access to a specific URL on your website based on an IP address, cookie, or Referer, mitigating CC attacks. To make your custom CC attack protection rules take effect, ensure that you have enabled CC attack protection.

Prerequisites

You have added the website you want to protect to WAF.

Constraints

  • It takes several minutes for a new rule to take effect. After the rule takes effect, protection events triggered by the rule will be displayed on the Events page.
  • If your website is connected to both WAF and Content Delivery Network (CDN) and the Protective Action is set to Verification code in the CC attack protection rule, set Path to a dynamic page.

Procedure

  1. Log in to the management console.
  2. Click in the upper left corner of the management console and select a region or project.
  3. Click in the upper left corner and choose Web Application Firewall under Security & Compliance.
  4. In the navigation pane on the left, choose Website Settings.
  1. In the Policy column of the row containing the domain name, click the number to go to the Policies page.
  2. In the CC Attack Protection configuration area, change Status if needed and click Customize Rule to go to the CC Attack Protection page.
  3. In the upper left corner of the CC Attack Protection page, click Add Rule.
  4. In the displayed dialog box, configure a CC attack protection rule by referring to Table 1.

    If a visitor whose cookie is name accesses a page on your website where the address includes /admin at the end (for example, https://www.example.com/adminlogic) more than 10 times within 60 seconds, WAF blocks the requests from visitors of the same cookie name for 600s and returns the page configured for Page Content.

    Table 1 Rule parameters

    Parameter

    Description

    Example Value

    Rate Limit Mode

    • Per IP address: A website visitor is identified by the IP address.
    • Per user: A website visitor is identified by the key value of Cookie or Header.
    • Other: A website visitor is identified by the Referer field (user-defined request source).
      NOTE:

      If you set Rate Limit Mode to Other, set Content of Referer to a complete URL containing the domain name. The Content field supports prefix match and exact match only, but cannot contain two or more consecutive slashes, for example, ///admin. If you enter ///admin, WAF will convert it to /admin.

      For example, if Path is /admin, and you do not want visitors to access the page from www.test.com, set Content of Referer to http://www.test.com.

    Per user

    Trigger

    Click Add to add conditions. At least one condition is required, but up to 30 conditions are allowed. If you add more than one condition, the rule will only take effect if all of the conditions are met.

    • Field: The options are Path, IP, Cookie, Header, and Params.
    • Subfield: Configure this field only when Cookie, Header, or Params is selected for Field.
      NOTICE:

      The length of a subfield cannot exceed 2048 bytes. Only digits, letters, underscores (_), and hyphens (-) are allowed.

    • Logic: Select a logical relationship from the drop-down list.
      NOTE:

      If you set Logic to Include any value, Exclude any value, Equal to any value, Not equal to any value, Prefix is any value, Prefix is not any of them, Suffix is any value, or Suffix is not any of them, select an existing reference table. For details, see Adding a Reference Table.

    • Content: Enter or select the content that matches the condition.

    Path Include /admin

    User Identifier

    This parameter is mandatory when you select Per user for Rate Limit Mode.

    • Cookie: A cookie field name. You need to configure an attribute variable name in the cookie that can uniquely identify a web visitor based on your website requirements. This field does not support regular expressions. Only complete matches are supported.

      For example, if a website uses the name field in the cookie to uniquely identify a website visitor, select name.

    • Header: Set the user-defined HTTP header you want to protect. You need to configure the HTTP header that can identify web visitors based on your website requirements.

    name

    Rate Limit

    The number of requests allowed from a website visitor in the rate limit period. If the number of requests exceeds the rate limit, WAF takes the action you configure for Protective Action.

    10 requests allowed in 60 seconds

    Protective Action

    The action that WAF will take if the number of requests exceeds Rate Limit you configured. The options are as follows:

    • Verification code: WAF allows requests that trigger the rule as long as your website visitors complete the required verification.
    • Block: WAF blocks requests that trigger the rule.
    • Block dynamically: WAF blocks requests that trigger the rule based on Allowable Frequency, which you configure after the first rate limit period is over.
    • Log only: WAF only logs requests that trigger the rule. You can download event data and view the protection logs of a specific domain name.

    Block

    Allowable Frequency

    This parameter can be set if you select Block dynamically for Protective Action.

    WAF blocks requests that trigger the rule based on Rate Limit first. Then, in the following rate limit period, WAF blocks requests that trigger the rule based on Allowable Frequency you configure.

    Allowable Frequency cannot be larger than Rate Limit.

    NOTE:

    If you set Allowable Frequency to 0, WAF blocks all requests that trigger the rule in the next rate limit period.

    8 requests allowed in 60 seconds

    Block Duration

    Period of time for which to block the item when you set Protective Action to Block.

    600 seconds

    Block Page

    The page displayed if the maximum number of requests has been reached. This parameter is configured only when Protective Action is set to Block.

    • If you select Default settings, the default block page is displayed.
    • If you select Custom, a custom error message is displayed.

    Custom

    Block Page Type

    If you select Custom for Block Page, select a type of block page. The options are:

    • application/jsontext/html
    • text/htmltext/xml
    • text/xml

    text/html

    Page Content

    If you select Custom for Block Page, configure the content to be returned.

    Page content styles corresponding to different page types are as follows:

    • text/html: <html><body>Forbidden</body></html>
    • application/json: {"msg": "Forbidden"}
    • text/xml: <?xml version="1.0" encoding="utf-8"?><error> <msg>Forbidden</msg></error>

    Rule Description

    A description of the rule. This parameter is optional.

    None

  5. Click Confirm. You can then view the added CC attack protection rule in the CC rule list.

    • To disable a rule, click Disable in the Operation column of the rule. The default Rule Status is Enabled.
    • To modify a rule, click Modify in the row containing the rule.
    • To delete a rule, click Delete in the row containing the rule.

Protection Effect

If you have configured a CC attack protection rule for your domain name, to verify WAF is protecting your website (www.example.com) against the configured CC attack protection rule:

  1. Clear the browser cache and enter the domain name in the address box of a browser to check whether the website is accessible.

    • If the website is inaccessible, connect the website domain name to WAF by following the instructions in Step 1: Add a Website to WAF.
    • If the website is accessible, go to Step 2.

  2. Clear the browser cache, enter http://www.example.com/admin in the address bar, and refresh the page 10 times within 60 seconds. In normal cases, the custom block page will be displayed the eleventh time you refresh the page, and the requested page will be accessible when you refresh the page 600 seconds later.

    If you select Verification code for protective action, a verification code is required for visitors to continue the access if they exceed the configured rate limit.

  3. Return to the WAF console. In the navigation pane, choose Events. On the displayed page, view or download events data.

Configuration Example - Verification Code

If domain name www.example.com has been connected to WAF, perform the following steps to verify that WAF CAPTCHA verification is enabled.

  1. Add a CC attack protection rule with Protection Action set to Verification code.
  2. Enable CC attack protection.
  3. Clear the browser cache and access http://www.example.com/admin/.

    If you access the page for 10 times within 60 seconds, a verification code is required when you attempt to access the page for the eleventh time. You need to enter the verification code to continue the access.

  4. Go to the WAF console. In the navigation pane on the left, choose Events. View the event on the Events page.