API Management service secure configuration for Standard v2 SKU

Use VNet Integration for Isolation

The Standard v2 SKU supports VNet Integration, which allows you to place the APIM instance in a private network. By doing so, you can:

• Isolate the APIM gateway from public internet traffic.
• Control inbound and outbound connectivity via Network Security Groups (NSGs) or Azure Firewall.

Key Steps:

• Integrate the APIM instance into a VNet (Internal mode). This ensures that only resources within the VNet or those with private endpoint connections can access it.
• Configure NSGs to allow traffic only from trusted sources.

 Secure Access with Azure Private Link

While the Standard v2 SKU doesn't support private endpoints for the management API itself, you can:

• Use Azure Private Link for connecting backend services securely to your APIM instance.
• Restrict management plane operations to trusted IP ranges by enabling Management IP Restrictions.

Key Steps:

1. Enable IP filtering for the management endpoints, restricting access to trusted ranges.
2. Use Azure role-based access control (RBAC) to govern access to the APIM service.

Use API Policies for Additional Security

Implement security policies directly within APIM to protect your APIs. Consider:

• Rate limiting and quotas to prevent abuse.
• IP restrictions or JWT validation policies to restrict access to APIs based on trusted sources or tokens.

Alternative Configuration with Automation

Since PowerShell cmdlets for APIM rely on the management API, you must secure API keys and access permissions:

• Store credentials securely in Azure Key Vault.
• Use Azure DevOps or automation scripts running in a secured environment (e.g., within a trusted VNet or Azure Bastion) to manage APIM configurations.

Security Recommendations

To comply with the OWASP API Security guidelines:

1. Use application gateways or reverse proxies in front of APIM for added protection.
2. Implement WAF (Web Application Firewall) policies to guard against threats.
3. Regularly review and rotate access keys (e.g., primary and secondary management keys).