JavaScript Interview Questions
  • JavaScript Interview Questions
  • Contact
  • Introduction
  • Question 1
  • Question 2
  • Question 3
  • Question 4
  • Question 5
  • Question 6
  • Question 7
  • Question 8
  • Question 9
  • Question 10
  • Question 11
  • Question 12
  • Question 13
  • Question 14
  • Question 15
  • Question 16
  • Question 17
  • Question 18
  • Question 19
  • Question 20
  • Question 21
  • Question 22
  • Question 23
  • Question 24
  • Question 25
  • Question 26
  • Question 27
  • Question 28
  • Question 29
  • Question 30
  • Question 31
  • Question 32
  • Question 33
  • Question 34
  • Question 35
  • Question 36
  • Question 37
  • Question 38
  • Question 39
  • Question 40
  • Question 41
  • Question 42
  • Question 43
  • Question 44
  • Question 45
  • Question 46
  • Question 47
  • Question 48
  • Question 49
  • Question 50
  • Question 51
  • Question 52
  • Question 53
  • Question 54
  • Question 55
  • Question 56
  • Question 57
  • Question 58
  • Question 59
  • Question 60
  • Question 61
  • Question 62
  • Question 63
  • Question 64
  • Question 65
  • Question 66
  • Question 67
  • Question 68
  • Question 69
  • Question 70
  • Question 71
  • Question 72
  • Question 73
  • Question 74
  • Question 75
  • Question 76
  • Question 77
  • Question 78
  • Question 79
  • Question 80
  • Question 81
  • Question 82
  • Question 83
  • Question 84
  • Question 85
  • Question 86
  • Question 87
  • Question 88
  • Question 89
  • Question 90
  • Question 91
  • Question 92
  • Question 93
  • Question 94
  • Question 95
  • Question 96
  • Question 97
  • Question 98
  • Question 99
  • Question 100
  • Epilogue
Powered by GitBook
On this page
  • Question
  • Answer

Question 95

Question

What are some common JavaScript security vulnerabilities, and how can they be prevented?

Answer

JavaScript's dynamic nature and client-side execution make it vulnerable to various attacks. Here are some common ones and how to prevent them:

1. Cross-Site Scripting (XSS):

  • The Problem: Attackers inject malicious scripts into websites, which then execute in the browsers of unsuspecting visitors. This can steal data, redirect users to harmful sites, or deface the website itself.

  • Prevention:

    • Input Sanitization: Always validate and escape user input before displaying it on the page. Use appropriate HTML encoding techniques (e.g., textContent instead of innerHTML) for user-provided text.

    • Output Encoding: Encode data properly when sending it to the browser to prevent it from being interpreted as code.

2. Cross-Site Request Forgery (CSRF):

  • The Problem: Attackers trick users into performing actions on a website without their knowledge, using hidden requests sent from a trusted site. This can lead to unauthorized account changes, data transfers, or other malicious actions.

  • Prevention:

    • CSRF Tokens: Use unique, unpredictable tokens generated server-side and included in every form submission. Verify these tokens on the server before processing requests.

3. SQL Injection:

  • The Problem: Attackers exploit vulnerabilities in web applications that use user input to construct SQL queries. Malicious SQL code can be injected to retrieve sensitive data, modify database contents, or even take control of the database server.

  • Prevention:

    • Parameterized Queries: Use parameterized queries (prepared statements) instead of directly embedding user input into SQL queries. This prevents attackers from injecting malicious code.

    • Input Validation & Sanitization: Carefully validate and sanitize all user-provided data before using it in any SQL statements.

4. Session Hijacking:

  • The Problem: Attackers steal a user's session ID (a unique identifier that allows access to their account), enabling them to impersonate the user and perform actions on their behalf.

  • Prevention:

    • Secure Cookies: Use HTTPS for all communication and set cookies with appropriate security flags (HttpOnly, Secure).

    • Session Timeout: Implement session timeouts to automatically invalidate sessions after a period of inactivity.

5. JavaScript Injection:

  • The Problem: Similar to XSS, but focuses specifically on injecting malicious JavaScript code into web pages or applications. This can lead to data theft, script execution, and other exploits.

  • Prevention:

    • Input Validation & Sanitization: Again, crucial! Validate and escape all user input that might be executed as JavaScript code.

Additional Tips:

  • Keep Software Updated: Regularly update your web server software, frameworks, libraries, and browser to patch known vulnerabilities.

  • Implement Access Control: Use role-based access control (RBAC) to restrict user permissions and minimize the potential impact of compromised accounts.

  • Security Testing: Conduct regular security testing, including penetration testing, to identify vulnerabilities in your applications and infrastructure.

PreviousQuestion 94NextQuestion 96

Last updated 6 months ago