An organization conducted a web application vulnerability assessment against the corporate website, and the following...

1. Analyze the Screenshot: The provided image shows a vulnerability scan report (likely from OWASP ZAP). The specific alert highlighted in blue is "Cross-Domain Misconfiguration" with 34 occurrences. In CompTIA performance-based questions, the highlighted item dictates the problem you need to solve.

2. Identify the Vulnerability: Cross-Domain Misconfiguration typically refers to issues with CORS (Cross-Origin Resource Sharing).

CORS is a mechanism that allows a server to indicate any other origins (domains, schemes, or ports) than its own from which a browser should permit loading of resources.

A common misconfiguration occurs when the server sends the header Access-Control-Allow-Origin: *. This wildcard tells the browser to allow any website to access the resources on your server, which defeats the browser's Same-Origin Policy protection.

3. Evaluate the Solution (Option C): To tune this and fix the vulnerability without breaking functionality for legitimate partners, the analyst should change the configuration from a wildcard (*) to a specific allowlist.

Remediation: Set the Access-Control-Allow-Origin header to strictly define which authorized domains (e.g., https://partner.example.com) are allowed to access the resources.

This aligns perfectly with Option C.

Why the other options are incorrect:

A. Set an HttpOnly flag to force communication by HTTPS:

This is incorrect for two reasons. First, it addresses the "Cookie No HttpOnly Flag" alert, not the highlighted "Cross-Domain" alert. Second, the definition is technically wrong: the HttpOnly flag prevents client-side scripts (like JavaScript) from accessing cookies (mitigating XSS); it does not force HTTPS. The Secure flag or HSTS headers are used to force HTTPS.

B. Block requests without an X-Frame-Options header:

This is the remediation for Clickjacking (seen in the alert list as "Missing Anti-clickjacking Header"), not Cross-Domain Misconfiguration.

D. Disable the cross-origin resource sharing header:

While removing the header entirely defaults the browser back to the strict Same-Origin Policy (which is secure), "tuning" implies adjusting the setting to work correctly. If the application requires cross-domain communication (which the presence of the header suggests), disabling it entirely would break the application. Configuring it correctly (Option C) is the professional remediation.