External DNS/http interaction vulnerability and External host header injection vulnerability.

Question

Hi team,
I am facing External DNS/http interaction vulnerability and External host header injection vulnerability.
Configured Environment details are:

1. Application gateway
2. Waf policy
3. Linux App service
4. Angular application

Answer 1

Hi @Omkar Talekar
To mitigate the External DNS/http interaction and External host header injection vulnerabilities in your setup with Application Gateway, WAF policy, Linux App Service, and Angular application,

• Make sure the Application Gateway is securely configured to manage DNS requests, validate incoming traffic, and prevent backend services from being directly accessible externally.
• Apply Web Application Firewall (WAF) policies to defend against common web attacks, including host header injection, by filtering and monitoring HTTP requests.
• Set up your application to validate host headers, which helps block malicious headers that could be used to exploit your application or redirect traffic.
• Turn on logging and monitoring for your Application Gateway and WAF to spot and address any unusual DNS or HTTP activity.
• Regularly update your Application Gateway, WAF policies, and application code to address known security issues.

References:

• Using Application Gateway WAF to protect your applications
• Azure threat protection
• Operational Excellence recommendations
• Secure your application
  Let me know if you have any further assistances needed.