C6 - Application Security

Which of the following attacks is characterized by inserting malicious code into user inputs that are executed by a database?

• Directory traversal

• Cross-site scripting

• SQL injection

• Replay attack

Answer explanation

SQL injection is an attack where malicious code is inserted into user inputs, which are then executed by a database. This allows attackers to manipulate or access sensitive data, making it the correct choice.

What is the main purpose of input validation in web applications?

• Improve user interface speed

• Prevent cross-site scripting and injection attacks

• Speed up database queries

• Optimize resource usage

Answer explanation

The main purpose of input validation is to prevent cross-site scripting and injection attacks by ensuring that user inputs are safe and conform to expected formats, thus protecting the application from malicious inputs.

What security mechanism ensures that code has not been altered since it was published by the developer?

• Code obfuscation

• Code signing

• Code commenting

• Code reuse

Answer explanation

Code signing is a security mechanism that uses digital signatures to verify the authenticity and integrity of code, ensuring it has not been altered since its publication by the developer.

Which type of vulnerability occurs when a web server allows attackers to access files outside the intended directory structure?

• Command injection

• Directory traversal

• Buffer overflow

• Blind SQL injection

Answer explanation

The correct answer is 'Directory traversal'. This vulnerability allows attackers to access files outside the intended directory by manipulating file paths, potentially exposing sensitive information on the server.

What software development practice integrates security throughout the entire software lifecycle, including development and operations?

• Static code analysis

• Continuous deployment

• DevSecOps

• Waterfall development

Answer explanation

DevSecOps integrates security into every phase of the software lifecycle, ensuring that security practices are part of development and operations. This contrasts with other practices that may address security separately.

Which type of cross-site scripting attack involves malicious scripts stored on a server and executed whenever a user views the affected page?

• Reflected XSS

• Persistent XSS

• DOM-based XSS

• Blind XSS

Answer explanation

Persistent XSS involves malicious scripts stored on a server, which are executed whenever a user views the affected page. This distinguishes it from reflected and DOM-based XSS, which do not involve stored scripts.

What term refers to running applications in isolated environments to prevent interaction with critical system resources?

• Containerization

• Sandboxing

• Virtualization

• Encapsulation

Answer explanation

Sandboxing refers to running applications in isolated environments, preventing them from interacting with critical system resources. This ensures security and stability, making it the correct term for the question.

Which of the following best describes a Cross-site Request Forgery (CSRF) attack?

• An attack that injects malicious code into user input

• An attack that exploits a user's trust in a website to execute unauthorized commands

• An attack that steals data from the server by exploiting URL parameters

• An attack that forces a server to visit malicious URLs

Answer explanation

A Cross-site Request Forgery (CSRF) attack tricks a user into executing unwanted actions on a trusted site, leveraging the user's authenticated session to perform unauthorized commands.

What type of testing method involves executing code with invalid or random data to discover vulnerabilities such as crashes or leaks?

• Static analysis

• Dynamic analysis

• Fuzzing

• Regression testing

Answer explanation

Fuzzing is a testing method that involves executing code with invalid or random data to identify vulnerabilities like crashes or memory leaks. It is specifically designed to uncover issues that may not be found through other testing methods.

Which of the following would be the best defense against a session replay attack in web applications?

• Secure cookies with the SECURE attribute

• Encrypting database communications

• Using firewall ACLs

• Code reuse practices

Answer explanation

Secure cookies with the SECURE attribute ensure that cookies are only sent over HTTPS, protecting them from being intercepted during a session replay attack. This is crucial for maintaining session integrity.