What are the security implications of using third-party libraries and how can they be mitigated?
- Third-party libraries may introduce vulnerabilities
- Third-party libraries always enhance security
- Third-party libraries have no impact on security
- Third-party libraries only affect performance
Using third-party libraries in software development can introduce security vulnerabilities. These libraries may contain known or unknown security flaws. To mitigate these risks, developers should regularly update libraries to the latest secure versions, use security scanning tools, and perform code reviews to identify and address potential vulnerabilities.
What is the primary purpose of indexing in databases?
- Speed up data retrieval
- Reduce storage space
- Enhance data security
- Sort data alphabetically
The primary purpose of indexing in databases is to speed up data retrieval. Indexes provide a quick way to locate specific rows in a large database table, improving query performance. While indexing may use additional storage, its main benefit is optimizing data access.
You have been tasked with securing a web application against XSS and CSRF attacks. What combination of security headers, practices, and designs would you use to mitigate the risk of these attacks?
- Implement Content Security Policy (CSP) headers and use anti-CSRF tokens.
- Disable browser same-origin policies for enhanced security.
- Store sensitive data in cookies without encryption.
- Allow inline scripts and styles for flexibility.
Option (1) is correct. Implementing Content Security Policy (CSP) headers and using anti-CSRF tokens are effective measures to mitigate XSS and CSRF attacks. Options (2) and (4) are insecure practices that would increase vulnerability. Option (3) is incorrect as sensitive data should be encrypted, not stored in cookies without protection.
How does the Event Loop interact with the Worker Threads in Node.js for handling CPU-intensive tasks?
- The Event Loop directly executes CPU-intensive tasks within its own thread.
- The Event Loop manages CPU-intensive tasks by offloading them to separate Worker Threads.
- The Event Loop blocks until CPU-intensive tasks are completed.
- CPU-intensive tasks are not supported in Node.js.
The Event Loop in Node.js can interact with Worker Threads to handle CPU-intensive tasks. These Worker Threads run in the background, separate from the Event Loop, and can be used to prevent blocking the main thread when performing CPU-intensive operations, such as complex calculations.
Which of the following is true regarding buffer instances in Node.js?
- Buffers in Node.js are resizable, allowing you to change their size dynamically.
- Buffers can be directly manipulated using arithmetic operations like addition and subtraction.
- Buffers in Node.js are fixed in size once allocated and cannot be resized.
- Buffers automatically handle memory management, so there's no need to free memory explicitly.
Buffer instances in Node.js are fixed in size once allocated, meaning you cannot change their size dynamically. If you need a larger buffer, you would need to create a new one and copy the data if necessary. The other options are not accurate descriptions of buffer behavior in Node.js.
Why is it essential to include a README.md file when publishing a package to the NPM registry?
- It is not essential; it's optional.
- It provides information about the package, its usage, and documentation.
- It is used by NPM to verify the package's authenticity.
- It reduces the package's download size.
Including a README.md file is essential because it provides valuable information about the package, its usage, and documentation for users and potential contributors. While it's not mandatory, it is considered a best practice to include comprehensive documentation.
In Express.js, sensitive static files can be secured by implementing access restrictions on the static files directory.
- Size
- Permissions
- File
- Path
Implementing access restrictions, typically using file permissions, helps secure sensitive static files in Express.js. By restricting who can read or modify these files, you can prevent unauthorized access to sensitive data.
Why is it important to optimize database queries in a Node.js application?
- To improve application performance
- To increase database security
- To reduce the number of tables in the database
- To add more features to the application
Optimizing database queries is crucial in Node.js to improve application performance. Inefficient queries can lead to slower response times, increased resource consumption, and a poor user experience.
Which HTTP header is crucial for handling CORS in web applications?
- Access-Control-Allow-Origin
- Cross-Domain-Allow
- Allow-Access-Control
- Origin-Control-Allow
The crucial HTTP header for handling CORS in web applications is Access-Control-Allow-Origin. This header specifies which domains are allowed to access resources on the server. It plays a central role in configuring the CORS policy for a web server.
In JavaScript, every function has a ______ property that points to the object it was created from.
- object
- constructor
- instance
- funcObj
Every function in JavaScript has a constructor property that points to the object (constructor) it was created from. This property is useful for identifying the constructor function of an object.