Top 30 multiple-choice questions (MCQs) only focused on the Cross-Site Scripting (XSS) and Data Store Attacks in WEB Security covering below topics,along with their answers and explanations.
• Understanding how XSS attacks can lead to data store vulnerabilities.
• Explaining how attackers might inject malicious scripts to manipulate or steal data.
PRACTICE IT NOW TO SHARPEN YOUR CONCEPT AND KNOWLEDGE
1. What is Cross-Site Scripting (XSS)?
- A scripting language for web development
- A technique to enhance website design
- An attack where malicious scripts are injected into web pages
- A secure communication protocol
XSS is a type of security vulnerability that allows attackers to inject malicious scripts into web pages, leading to potential data theft or manipulation.
2. Which of the following is a potential consequence of a successful XSS attack?
- Server overload
- Data store compromise
- Improved website performance
- Enhanced user experience
XSS attacks can lead to data store compromise, allowing attackers to manipulate or steal sensitive information.
3. How does a stored XSS attack differ from a reflected XSS attack?
- Stored XSS involves persistent injection, while reflected XSS is non-persistent
- Reflected XSS involves persistent injection, while stored XSS is non-persistent
- Both stored and reflected XSS are non-persistent
- There is no difference between stored and reflected XSS
Stored XSS involves injecting malicious scripts that are permanently stored on a target server, while reflected XSS involves scripts that are only temporarily present in the server's response.
4. What is the primary purpose of an XSS payload?
- To enhance website design
- To manipulate or steal data
- To improve server performance
- To increase website traffic
An XSS payload is designed to manipulate or steal data by executing malicious scripts in the context of a user's browser.
5. Which of the following is an example of an XSS vector?
- https://www.example.com/login
- user123
- admin:password123
Option A is an example of an XSS vector, where a malicious script is injected using an image tag.
6. In a DOM-based XSS attack, where does the malicious script execute?
- Server-side
- Client-side
- Database
- Both server-side and client-side
DOM-based XSS attacks involve the execution of malicious scripts on the client-side, within the Document Object Model of the web page.
7. How can Content Security Policy (CSP) help mitigate XSS attacks?
- By encrypting data in transit
- By preventing the execution of inline scripts
- By increasing server bandwidth
- By enhancing user authentication
Content Security Policy (CSP) can help mitigate XSS attacks by restricting the execution of inline scripts, reducing the attack surface.
8. What is the purpose of input validation in preventing XSS attacks?
- To encrypt data during transmission
- To sanitize user input and remove malicious characters
- To increase server performance
- To enhance user authentication
Input validation helps prevent XSS attacks by sanitizing user input and removing or neutralizing potentially malicious characters.
9. Which type of XSS attack occurs when the attacker injects malicious scripts that are then executed by other users?
- Stored XSS
- Reflected XSS
- DOM-based XSS
- Blind XSS
Stored XSS involves injecting malicious scripts that are permanently stored on a target server and executed when other users access the affected page.
10. What is the potential impact of an XSS attack on user data?
- Improved data integrity
- Enhanced data confidentiality
- Manipulation or theft of user data
- Increased data availability
The potential impact of an XSS attack includes the manipulation or theft of user data, as attackers can execute scripts in the context of a user's browser.
11. What is the main goal of an attacker in a Cross-Site Scripting (XSS) attack?
- To improve website design
- To gain unauthorized access to the server
- To manipulate or steal data from users
- To enhance server performance
The primary goal of an attacker in an XSS attack is to manipulate or steal data from users.
12. Which of the following best describes a "same-origin policy" in the context of web security?
- Allowing any script to access any resource on the web
- Restricting scripts from making requests to a different origin
- Allowing scripts to execute without any restrictions
- Enabling cross-origin resource sharing without limitations
The "same-origin policy" restricts scripts from making requests to a different origin to prevent security vulnerabilities like XSS.
13. What is the difference between stored XSS and reflected XSS?
- Stored XSS is persistent, while reflected XSS is non-persistent
- Reflected XSS is persistent, while stored XSS is non-persistent
- Both stored and reflected XSS are persistent
- There is no difference between stored and reflected XSS
Stored XSS involves persistently injecting malicious scripts, while reflected XSS is non-persistent.
14. How can the HttpOnly flag in cookies help mitigate XSS attacks?
- By preventing the cookie from being accessed through JavaScript
- By allowing any script to access the cookie
- By encrypting the cookie data
- By increasing server bandwidth
The HttpOnly flag prevents the cookie from being accessed through JavaScript, reducing the risk of XSS attacks.
15. What is the primary risk associated with DOM-based XSS attacks?
- Server overload
- Data store compromise
- Client-side script execution
- Session hijacking
DOM-based XSS attacks involve the execution of malicious scripts on the client side.
16. What role does the "sandbox" attribute play in mitigating XSS attacks?
- It prevents the execution of inline scripts
- It restricts the capabilities of an iframe's content
- It encrypts data during transmission
- It increases server performance
The "sandbox" attribute restricts the capabilities of an iframe's content, helping to mitigate XSS attacks.
17. What is the purpose of input sanitization in the context of XSS prevention?
- To encrypt data during transmission
- To restrict user access to the server
- To remove or neutralize potentially malicious characters in user input
- To enhance server performance
Input sanitization removes or neutralizes potentially malicious characters in user input to prevent XSS attacks.
18. In a reflected XSS attack, where is the injected malicious script typically found?
- In a server-side database
- In the response from the server to the user
- In a client-side cookie
- In the web browser's cache
In reflected XSS, the injected script is typically found in the response from the server to the user.
19. What is the primary purpose of the "nonce" attribute in preventing XSS attacks?
- To enhance website design
- To improve server performance
- To generate random numbers
- To prevent the execution of unauthorized scripts
The "nonce" attribute is used to prevent the execution of unauthorized scripts by allowing only scripts with a specific nonce value to run.
20. How can security headers like Content Security Policy (CSP) be used to mitigate XSS attacks?
- By encrypting data in transit
- By preventing the execution of inline scripts and controlling allowed sources
- By increasing server bandwidth
- By enhancing user authentication
Security headers like Content Security Policy (CSP) can mitigate XSS attacks by preventing the execution of inline scripts and controlling allowed sources.
21. What is a potential risk associated with insecure file uploads on a web application?
- Improved user experience
- Increased server performance
- Remote code execution
- Enhanced data integrity
Insecure file uploads may lead to remote code execution, allowing attackers to execute arbitrary code on the server.
22. How can an attacker exploit a file upload vulnerability to compromise a server?
- By enhancing user authentication
- By injecting SQL queries
- By uploading malicious files with executable code
- By encrypting data in transit
An attacker can exploit a file upload vulnerability by uploading malicious files containing executable code, which can compromise the security of the server.
