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Manage notifications and custom reactions for WAF

What are triggers?

Triggers are tools that allow you to receive notifications and set how WAF should react to some events that it doesn't respond to by default (e.g., behavior attacks.)

With triggers, you can:

  • Get notified about significant events through your daily workflow tools, like corporate messengers or incident management systems
  • Block IP addresses that have sent a certain number of requests or attack vectors
  • Detect behavioral attacks based on the number of requests made to specific API endpoints
  • Streamline the event list by grouping hits from the same IP address into a single attack
  • Monitor a rise in malicious requests detected by WAF nodes, which could suggest an ongoing attack, allowing for timely actions, such as manually blocking the attacker's IP addresses, to mitigate the threat

Each trigger consists of three components:

  1. Condition is an event for which the WAF reaction is configured.
  2. Filters are additional criteria that detail the conditions.
  3. Reaction is the action the WAF will perform if the event meets the added condition and filter.

Let's say, for example, that you want to receive alerts about XSS attacks (if there are more than 2,000 per hour) via email. In this case, you should create a trigger with the following components:

  • Condition: The number of attacks and the value of 2,000 per hour for it.
  • Filter: XSS attack type.
  • Reaction: A message and the e-mail address for integration.

Triggers are managed and collected in the Triggers tab.


Create triggers

  1. Click Create trigger.
  2. Choose conditions.
  3. Add filters.
  4. Add reactions.
  5. Save the trigger.

Now let's explore how steps 2-5 work.

Step 2. Choose a condition

A condition refers to a system event that you would like to be alerted about. The following conditions are available for notification:

  • Brute force: Brute force attacks include brute-forcing passwords, session IDs, and account data spoofing. Signs of brute forcing include sending many requests to the same endpoint during the defined time interval.
  • Forced browsing: Forced browsing is a behavioral attack in which an attacker tries to find directories and files with information about an application's configuration and components. Signs of forced browsing include sending many requests to different endpoints, to which the application responds with a 404 code.
  • BOLA: BOLA (broken object-level authorization) is a behavioral attack in which an attacker can retrieve or modify an application component by identity through an API, thus bypassing authorization. This attack exploits a vulnerability related to the lack of, or insufficient verification of, access rights.
  • Weak JWT: Dash please add an explanation about Weak JWT on the line above
  • Number of attack vectors (malicious payloads): A malicious payload is the part of a request that contains instructions about what actions should be performed in an attacked application. With a trigger, you can specify how many requests with payloads WAF should react to.
  • Number of attacks, hits, incidents: With conditions 5–7, you'll set the number of attacks, hits, or incidents about which the WAF should send you an e-mail notification.
  • Denylisted IP: Specify blocked IPs.
  • Changes in API inventory: As above, please add a basic explanation
  • Hits from the same IP: Using a condition, you can specify the threshold from which hits sent from the same IP should be grouped into a single attack in the Events section.
Conditions WAF

Choose a condition and set the lower threshold for the reaction, if the setting is available.

Step 3. Add a filter

Filters are used for condition detailing. For example, you can set up reactions to attacks of certain types, such as brute-force attacks and SQL injections.

The following filters are available:

  • URI (only for Brute force, Forced browsing, and BOLA) is the endpoint to which the requests were sent.
  • Type is the type of attack in the request or the application vulnerability where an exploit attempt occurred.
  • Application is the application that received the request or in which the request was found.
  • IP is the IP address from which the request was sent.
  • Domain is the domain of the application to which the request was sent or where the incident was found.
  • Response status is the code with which the application responded to the request.
  • Target is part of the application ('Database', 'Server', or 'Client') that was attacked or in which part of the application the vulnerability was found.

Choose one or more filters and set values for them.

Type filter WAF

Step 4. Add reactions

The reaction determines what WAF should do if a request fits the condition and filters (if they were set). The set of available reactions also depends on the selected condition.

We list all available reactions below.

  • Mark the requests as brute-force or forced browsing attacks. Requests will be marked as attacks in the events list but will not be blocked. To block requests, you can add an additional reaction: denylist IP address.
  • Mark the requests as BOLA attacks. Requests will be marked as attacks in the events list but will not be blocked. To block requests, you can add an additional reaction: denylist IP address.
  • Record the JWT vulnerability.
  • Add IP to the denylist.
  • Add IP to the graylist.
  • Send a notification to the SIEM system or Webhook URL configured in the (should be preconfigured by technical support).
  • Send a notification to the messenger (should be preconfigured by technical support). Dash plz check lines 107 and 108 endings in brackets, looks weird and maybe needs fixing.

Select one or more reactions. The reactions applicable to the condition are found under the Number of attacks section:

Add a reaction WAF

Step 5. Save the trigger

1. Click Create in the trigger creation modal dialog.

2. Specify the trigger's name and description (if required) and click Done.

Disable or delete a trigger

Go to the Triggers tab, click the three dots next to the trigger you want to disable or delete, click the relevant option, and confirm the action when prompted.

Disable or delete a trigger


  • If you disable a trigger, reactions for the trigger will be stopped until the trigger is enabled again. The disabled triggers are displayed in the list. To re-enable, use the Enable option.
  • If you delete a trigger, it'll be permanently stopped and removed from the general list forever.

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