CompTIA Updated CS0-003 Exam Questions and Answers by klara

Under the terms of PCI DSS, an organization that has experienced a breach of customer transactions should report the breach to the card issuer. The card issuer is the financial institution that issues the payment cards to the customers and that is responsible for authorizing and processing the transactions. The card issuer may have specific reporting requirements and procedures for the organization to follow in the event of a breach. The organization should also notify other parties that may be affected by the breach, such as customers, law enforcement, or regulators, depending on the nature and scope of the breach. Official References: https://www.pcisecuritystandards.org/

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.

D (4: HTTPS traffic to an external IP - 5.29.1.5)

The log entry shows an internal system (172.16.1.30) communicating with an external IP (5.29.1.5) overTCP 443 (HTTPS)usingBrowser.exe.

HTTPS traffic to an unknown external IP could indicate data exfiltration, as attackers often use encrypted channels to disguise stolen data transfers.

G (7: FTP traffic to an external backup server - bank.backup.com)

The log entry indicates that an internal machine (172.16.1.25) is transferring data tobank.backup.comusingFTP (port 21)andFileZilla.

FTP is a major concern because it is an outdated, unencrypted protocolthat can be exploited for data exfiltration. If unauthorized, this could be a serious data breach.

Other Options:

A (ARP traffic) → Not a concern(Just address resolution)

B (RPC Kerberos traffic) → Normal for authentication

C (SMB traffic) → Internal file sharing

**E (DNS traffic) → Common, though could be exfiltration in some cases, but not in this log)

F (WUS traffic) → Appears to be Windows Update Service traffic, likely legitimate

The snippet shows an attempt to access the boot.ini file, which is a configuration file for Windows operating systems. The “… \ … /” pattern is used to navigate up the directory structure and reach the root directory, where the boot.ini file is located. This is a common technique for exploiting directory traversal vulnerabilities, which allow an attacker to access files and directories outside the intended web server path. The other options are not relevant for this purpose: remote file inclusion involves injecting a malicious file into a web application; cross-site scripting involves injecting malicious scripts into a web page; remote code execution involves executing arbitrary commands on a remote system; enumeration of /etc/passwd involves accessing the file that stores user information on Linux systems.