CompTIA CASP+ Practice Test

What type of vulnerability can arise from the given JavaScript code snippet?

1. SQL injection.

2. Cross-site scripting (XSS).

3. Buffer overflow.

4. Access control violation.

The correct answer is: Cross-site scripting (XSS).

The vulnerability that arises from the JavaScript code snippet is Cross-site scripting (XSS). This type of vulnerability occurs when an application includes untrusted data in a web page without proper validation or escaping. An attacker can exploit this flaw by injecting malicious scripts into the web pages viewed by other users, executing those scripts in the context of their browsers. This can lead to various harmful actions, such as stealing cookies, session tokens, or other sensitive information. XSS vulnerabilities typically occur in web applications where user input is processed and reflected back to other users without proper sanitization. For example, if a JavaScript snippet takes input from a user and outputs it directly onto a webpage, without adequate checks, an attacker could submit a script tag or other JavaScript code that will execute in the browser of any user viewing that webpage. In contrast, SQL injection is a different category of vulnerability, which involves manipulating SQL queries. Buffer overflow pertains to issues related to memory management, often seen in languages like C or C++. Access control violations involve improper handling of permissions and roles within an application, which does not relate directly to the execution of client-side scripts like JavaScript.