Server-Side Request Forgery (SSRF)

Mitigating Server-Side Request Forgery (SSRF) vulnerabilities is crucial to prevent attackers from making unauthorized requests to internal or external resources through your application. The mitigation techniques for SSRF are language-agnostic, and you should follow best practices in any programming language. Here's how to mitigate SSRF in various languages:

General Tips (Applicable to All Languages):

1. **Input Validation:** Sanitize and validate user inputs, especially when they are used to construct URLs for external requests. Avoid using untrusted input to build URLs for requests.

2. **Whitelist Allowed Hosts:** Maintain a whitelist of allowed domains or IP addresses that your application is permitted to access. Ensure that requests are made only to these trusted sources.

3. **Use Libraries with URL Whitelisting:** When making HTTP requests, consider using libraries that support URL whitelisting, which can help restrict requests to safe destinations.

4. **Avoid User-Controlled URLs:** Do not allow user-controlled inputs to determine the destination of external requests.

5. **HTTP Libraries:** When making HTTP requests, consider using HTTP libraries or frameworks that support URL whitelisting, which can help mitigate SSRF.

6. **Security Audits:** Regularly audit your code for SSRF vulnerabilities and use security scanning tools to detect potential issues.

7. **Least Privilege:** If possible, run your application with minimal privileges to limit the potential impact of SSRF attacks.

By following these best practices and treating user inputs as untrusted, you can significantly reduce the risk of SSRF vulnerabilities in your applications, regardless of the programming language you're using.