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Event Information

  • The DeleteRule event in AWS WAF refers to the action of deleting a rule from a Web Application Firewall (WAF) configuration.
  • When this event occurs, it means that a specific rule, which is used to define the conditions for allowing or blocking web requests, has been removed from the WAF configuration.
  • This event is typically triggered when an administrator or an automated process decides to remove a rule that is no longer needed or has become obsolete in the WAF configuration.

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Examples

  1. Unauthorized deletion of WAF rules: If security is impacted with DeleteRule in AWS WAF, an example could be an attacker gaining access to the AWS account and deleting critical WAF rules. This could result in the bypassing of security controls and exposing the application to potential attacks.

  2. Misconfiguration leading to rule deletion: Another example could be a misconfiguration in the AWS WAF settings, where an administrator accidentally deletes a rule that is essential for protecting the application. This could leave the application vulnerable to various types of attacks, such as SQL injection or cross-site scripting.

  3. Insider threat: A malicious insider with access to the AWS account could intentionally delete WAF rules to bypass security measures and gain unauthorized access to sensitive data or disrupt the application. This could result in data breaches, service disruptions, or other security incidents.

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Remediation

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Using Console

  1. Identify the specific AWS WAF rule that needs to be remediated based on the examples provided.

    • Log in to the AWS Management Console and navigate to the AWS WAF service.
    • Select the appropriate web ACL that contains the rule that needs to be remediated.

  2. Modify the AWS WAF rule to address the identified issue.

    • Within the selected web ACL, locate the rule that needs to be remediated.
    • Click on the rule to access its configuration settings.
    • Adjust the rule’s parameters or conditions to align with the desired remediation action.
    • Save the changes made to the rule.

  3. Test and monitor the remediated AWS WAF rule.

    • Deploy the updated web ACL to the appropriate AWS resources (e.g., Amazon CloudFront distribution, Application Load Balancer).
    • Monitor the traffic and behavior of the protected resources to ensure that the remediated rule is functioning as expected.
    • Continuously monitor and analyze the AWS WAF logs and metrics to identify any potential issues or anomalies that may require further remediation.

Note: The specific steps may vary depending on the AWS WAF console interface and the nature of the rule being remediated. It is important to refer to the AWS documentation for detailed instructions and best practices.

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Using CLI

  1. To remediate a specific rule in AWS WAF using AWS CLI, you can use the update-rule command. For example, if you want to update a rule with the ID “12345678-1234-1234-1234-123456789012” in a WebACL named “MyWebACL”, you can use the following command:
aws wafv2 update-rule --name MyWebACL --scope REGIONAL --id 12345678-1234-1234-1234-123456789012 --action ALLOW --override-action NONE

This command updates the specified rule to allow the traffic and sets the override action to none.

  1. To remediate a rate-based rule in AWS WAF using AWS CLI, you can use the update-rate-based-rule command. For example, if you want to update a rate-based rule with the ID “12345678-1234-1234-1234-123456789012” in a WebACL named “MyWebACL”, you can use the following command:
aws wafv2 update-rate-based-rule --name MyWebACL --scope REGIONAL --id 12345678-1234-1234-1234-123456789012 --rate-key IP --rate-limit 1000

This command updates the specified rate-based rule to limit the requests from a specific IP address to 1000 requests per 5 minutes.

  1. To remediate a managed rule group in AWS WAF using AWS CLI, you can use the update-managed-rule-set-version command. For example, if you want to update a managed rule group named “AWSManagedRulesCommonRuleSet” to the latest version in a WebACL named “MyWebACL”, you can use the following command:
aws wafv2 update-managed-rule-set-version --name MyWebACL --scope REGIONAL --managed-rule-set-name AWSManagedRulesCommonRuleSet --version 3.1

This command updates the specified managed rule group to the latest version (3.1) available in AWS WAF.

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Using Python

  1. Example 1: Blocking IP addresses with AWS WAF using Python:
    • Use the AWS SDK for Python (Boto3) to interact with AWS WAF.
    • Write a Python script to retrieve the IP addresses that need to be blocked.
    • Use the create_ip_set method to create an IP set in AWS WAF.
    • Use the update_ip_set method to add the IP addresses to the IP set.
    • Use the update_web_acl method to associate the IP set with the desired web ACL.
import boto3

# Create AWS WAF client
waf_client = boto3.client('waf')

# Retrieve IP addresses to block
ip_addresses = ['192.0.2.1', '203.0.113.2']

# Create IP set
response = waf_client.create_ip_set(
    Name='BlockedIPSet',
    ChangeToken='CHANGE_TOKEN'
)

# Add IP addresses to IP set
response = waf_client.update_ip_set(
    IPSetId='IP_SET_ID',
    ChangeToken='CHANGE_TOKEN',
    Updates=[
        {
            'Action': 'INSERT',
            'IPSetDescriptor': {
                'Type': 'IPV4',
                'Value': ip_address
            }
        }
        for ip_address in ip_addresses
    ]
)

# Associate IP set with web ACL
response = waf_client.update_web_acl(
    WebACLId='WEB_ACL_ID',
    ChangeToken='CHANGE_TOKEN',
    Updates=[
        {
            'Action': 'INSERT',
            'ActivatedRule': {
                'Priority': 1,
                'RuleId': 'BLOCK_RULE_ID',
                'Action': {
                    'Type': 'BLOCK'
                }
            }
        }
    ]
)
  1. Example 2: Enabling AWS WAF rate-based rules using Python:
    • Use the AWS SDK for Python (Boto3) to interact with AWS WAF.
    • Write a Python script to enable rate-based rules for a specific web ACL.
    • Use the create_rate_based_rule method to create a rate-based rule.
    • Use the update_web_acl method to associate the rate-based rule with the desired web ACL.
import boto3

# Create AWS WAF client
waf_client = boto3.client('waf')

# Create rate-based rule
response = waf_client.create_rate_based_rule(
    Name='RateBasedRule',
    MetricName='RateBasedRule',
    RateKey='IP',
    RateLimit=1000,
    ChangeToken='CHANGE_TOKEN'
)

# Associate rate-based rule with web ACL
response = waf_client.update_web_acl(
    WebACLId='WEB_ACL_ID',
    ChangeToken='CHANGE_TOKEN',
    Updates=[
        {
            'Action': 'INSERT',
            'ActivatedRule': {
                'Priority': 1,
                'RuleId': 'RATE_BASED_RULE_ID',
                'Action': {
                    'Type': 'COUNT'
                }
            }
        }
    ]
)
  1. Example 3: Creating AWS WAF rules to block SQL injection using Python:
    • Use the AWS SDK for Python (Boto3) to interact with AWS WAF.
    • Write a Python script to create AWS WAF rules to block SQL injection.
    • Use the create_rule method to create a rule for SQL injection.
    • Use the update_web_acl method to associate the rule with the desired web ACL.
import boto3

# Create AWS WAF client
waf_client = boto3.client('waf')

# Create rule for SQL injection
response = waf_client.create_rule(
    Name='SQLInjectionRule',
    MetricName='SQLInjectionRule',
    ChangeToken='CHANGE_TOKEN',
    Predicates=[
        {
            'DataId': 'SQL_INJECTION_DATA_ID',
            'Negated': False,
            'Type': 'SQLi'
        }
    ]
)

# Associate rule with web ACL
response = waf_client.update_web_acl(
    WebACLId='WEB_ACL_ID',
    ChangeToken='CHANGE_TOKEN',
    Updates=[
        {
            'Action': 'INSERT',
            'ActivatedRule': {
                'Priority': 1,
                'RuleId': 'SQL_INJECTION_RULE_ID',
                'Action': {
                    'Type': 'BLOCK'
                }
            }
        }
    ]
)