Azure Web Application Firewall Skill

This skill provides expert guidance for Azure Web Application Firewall. Covers troubleshooting, best practices, decision making, limits & quotas, security, configuration, integrations & coding patterns, and deployment. It combines local quick-reference content with remote documentation fetching capabilities.

How to Use This Skill

> IMPORTANT for Agent: Use the Category Index below to locate relevant sections. For categories with line ranges (e.g., L35-L120), use read_file with the specified lines. For categories with file links (e.g., [security.md](security.md)), use read_file on the linked reference file

> IMPORTANT for Agent: If metadata.generated_at is more than 3 months old, suggest the user pull the latest version from the repository. If mcp_microsoftdocs tools are not available, suggest the user install it: Installation Guide

This skill requires network access to fetch documentation content:

• Preferred: Use mcp_microsoftdocs:microsoft_docs_fetch with query string from=learn-agent-skill. Returns Markdown.
• Fallback: Use fetch_webpage with query string from=learn-agent-skill&accept=text/markdown. Returns Markdown.

Category Index

| Category | Lines | Description | |----------|-------|-------------| | Troubleshooting | L36-L40 | Diagnosing and fixing Azure WAF issues on Front Door and Application Gateway, including rule matches, false positives, blocked requests, and configuration or logging problems. | | Best Practices | L41-L48 | Best practices for configuring, tuning, and hardening WAF on Front Door and Application Gateway, including geomatch rules, exclusions, and security posture improvements. | | Decision Making | L49-L54 | Guidance on planning and migrating from legacy WAF configs to full WAF policies, and managing the lifecycle, upgrades, and versions of Azure WAF managed rule sets. | | Limits & Quotas | L55-L60 | Details on WAF limits like max request/body size, file upload constraints, rule engine behavior under high load, and how to configure or tune these limits on Application Gateway. | | Security | L61-L70 | Configuring and governing WAF security: IP restrictions, DRS rule groups, exclusions/exceptions, hardening settings, and enforcing policies with Azure Policy. | | Configuration | L71-L110 | Configuring Azure WAF (Front Door & Application Gateway): custom/managed rules, rate limiting, geo/bot protection, exclusions, logging/sensitive data protection, and policy scoping/association. | | Integrations & Coding Patterns | L111-L121 | Using WAF with other Azure services: integrating logs with Sentinel/Log Analytics, automating incident response, investigating events, and protecting APIM/Azure OpenAI via Front Door WAF. | | Deployment | L122-L128 | How to deploy and manage Application Gateway WAF v2 using Bicep, ARM templates, Terraform, and upgrade existing WAF configurations to WAF policies. |

Troubleshooting

| Topic | URL | |-------|-----| | Troubleshoot Azure Front Door WAF behavior and rules | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-faq |

Best Practices

| Topic | URL | |-------|-----| | Implement WAF best practices in Azure Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-best-practices | | Tune Azure Front Door WAF rules and exclusions | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-tuning | | Apply best practices for WAF on Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/best-practices | | Apply geomatch WAF rules to strengthen web app security | https://learn.microsoft.com/en-us/azure/web-application-firewall/geomatch-custom-rules-examples |

Decision Making

| Topic | URL | |-------|-----| | Migrate Azure Application Gateway WAF configs to full policies | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/migrate-policy | | Plan Azure WAF managed ruleset lifecycle and upgrades | https://learn.microsoft.com/en-us/azure/web-application-firewall/ruleset-support-policy |

Limits & Quotas

| Topic | URL | |-------|-----| | Understand Azure Application Gateway WAF limits and behavior | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-waf-faq | | Configure WAF request and file upload size limits on Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-waf-request-size-limits |

Security

| Topic | URL | |-------|-----| | Configure IP restriction rules in Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-configure-ip-restriction | | Understand Azure WAF Front Door DRS rule groups | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-drs | | Configure WAF exclusion lists for Azure Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-exclusion | | Configure WAF exception lists for Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-exceptions | | Harden Azure WAF with security configurations | https://learn.microsoft.com/en-us/azure/web-application-firewall/secure-web-application-firewall | | Enforce WAF governance using Azure Policy | https://learn.microsoft.com/en-us/azure/web-application-firewall/shared/waf-azure-policy |

Configuration

| Topic | URL | |-------|-----| | Configure CAPTCHA challenges in Azure Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/captcha-challenge | | Configure WAF exception lists for Azure Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/front-door-exceptions | | Configure custom block responses for Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-configure-custom-response-code | | Define custom WAF rules for Azure Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-custom-rules | | Configure Azure Front Door WAF custom and managed rules | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-custom-rules-powershell | | Set up WAF exclusion rules on Azure Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-exclusion-configure | | Configure geo-filtering rules in Azure Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-geo-filtering | | Configure monitoring and logging for Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-monitor | | Enable and configure bot protection in Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-policy-configure-bot-protection | | Configure Azure Front Door WAF policy-level settings | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-policy-settings | | Configure rate limiting policies in Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-rate-limit | | Create and tune WAF rate-limit rules on Front Door | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-rate-limit-configure | | Create a geo-filtering WAF policy with PowerShell | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-front-door-tutorial-geo-filtering | | Configure log scrubbing on Azure Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-sensitive-data-protection-configure-frontdoor | | Enable sensitive data protection for Front Door WAF logs | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/waf-sensitive-data-protection-frontdoor | | Reference for Application Gateway WAF CRS and DRS rules | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-crs-rulegroups-rules | | Customize Application Gateway WAF rules using Azure CLI | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-customize-waf-rules-cli | | Customize Application Gateway WAF rules in Azure portal | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-customize-waf-rules-portal | | Customize Application Gateway WAF rules with PowerShell | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-customize-waf-rules-powershell | | Configure WAF exclusion lists on Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-waf-configuration | | Configure and analyze Application Gateway WAF metrics | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/application-gateway-waf-metrics | | Associate WAF policies with existing Application Gateways | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/associate-waf-policy-existing-gateway | | Configure bot protection rules for Azure Application Gateway WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/bot-protection | | Configure custom WAF response for Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/configure-custom-response-code | | Create WAF v2 custom rules with Azure PowerShell | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/configure-waf-custom-rules | | Create and attach WAF policies to Azure Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/create-waf-policy-ag | | Use Application Gateway WAF Insights dashboards | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/insights | | Configure per-site WAF policies with PowerShell | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/per-site-policies | | Understand and scope WAF policies on Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/policy-overview | | Create rate-limiting custom rules for Application Gateway WAF v2 | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/rate-limiting-configure | | Configure rate limiting for Azure Application Gateway WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/rate-limiting-overview | | Configure sensitive data protection in WAF logs | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/waf-sensitive-data-protection | | Set up WAF log scrubbing on Application Gateway | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/waf-sensitive-data-protection-configure | | Enable and manage logging for Azure WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/web-application-firewall-logs | | Manage WAF policies centrally with Azure Firewall Manager | https://learn.microsoft.com/en-us/azure/web-application-firewall/shared/manage-policies | | Use JavaScript challenge for bot mitigation in WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/waf-javascript-challenge |

Integrations & Coding Patterns

| Topic | URL | |-------|-----| | Automate WAF incident response with Microsoft Sentinel | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/automated-detection-response-with-sentinel | | Protect APIM-hosted APIs with Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/protect-api-hosted-apim-by-waf | | Secure Azure OpenAI endpoints using Front Door WAF | https://learn.microsoft.com/en-us/azure/web-application-firewall/afds/protect-azure-open-ai | | Analyze Application Gateway WAF logs with Log Analytics | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/log-analytics | | Investigate Azure WAF events with Security Copilot | https://learn.microsoft.com/en-us/azure/web-application-firewall/waf-copilot | | Detect new web threats using WAF and Sentinel | https://learn.microsoft.com/en-us/azure/web-application-firewall/waf-new-threat-detection | | Integrate Azure WAF logs with Microsoft Sentinel | https://learn.microsoft.com/en-us/azure/web-application-firewall/waf-sentinel |

Deployment

| Topic | URL | |-------|-----| | Deploy Azure Application Gateway WAF v2 using Bicep | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/quick-create-bicep | | Deploy Azure Application Gateway WAF v2 via ARM template | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/quick-create-template | | Upgrade Azure Application Gateway WAF configuration to policy | https://learn.microsoft.com/en-us/azure/web-application-firewall/ag/upgrade-ag-waf-policy | | Provision Application Gateway WAF v2 with Terraform | https://learn.microsoft.com/en-us/azure/web-application-firewall/quickstart-web-application-firewall-terraform |