Business information leak - Personal Information
Need
Protection of personal information from unauthorized access or leakage
Context
- Usage of C# 7.0 for modern and efficient programming in the C# language
- Usage of Microsoft.AspNetCore.Mvc for building web applications using the MVC pattern in .NET Core
Description
Non compliant code
public class User
{
public string Id { get; set; }
public string PhoneNumber { get; set; }
}
public class UserController : Controller
{
[HttpPost]
public IActionResult CreateUser(User user)
{
// Storing user information in the source code
var userId = "1234567890"; // Real ID
var userPhoneNumber = "123-456-7890"; // Real Phone Number
return Ok();
}
}
The above code is a representation of a simple user creation endpoint in an ASP.NET Core application. The User
class holds two properties, Id
and PhoneNumber
, which are expected to be provided when creating a new user.
The vulnerability lies within the CreateUser
method of the UserController
. Here, the developer has hard-coded real user information - an ID and a phone number - directly into the source code. This is a major security risk, as anyone with access to the source code can now view this sensitive information.
Hard-coding sensitive information into the source code is a bad practice and can lead to serious data leaks and security breaches. This is especially true for version control systems where the source code is stored, as every change is tracked and can be viewed at any time.
This vulnerability can be exploited by an attacker who gains access to the source code, allowing them to steal the hard-coded information and potentially use it for malicious purposes.
Steps
- Do not store sensitive information such as real ID numbers and phone numbers in the source code.
- Implement a secure data storage mechanism such as a database to store user information.
- Use appropriate encryption techniques to protect sensitive data at rest and in transit.
- Implement access controls and authentication mechanisms to restrict access to sensitive information.
- Follow security best practices and guidelines provided by the ASP.NET Core framework.
Compliant code
public class User
{
public string Id { get; set; }
public string PhoneNumber { get; set; }
}
public class UserController : Controller
{
private readonly IUserService _userService;
public UserController(IUserService userService)
{
_userService = userService;
}
[HttpPost]
public async Task<IActionResult> CreateUser(User user)
{
// Storing user information in the database
var result = await _userService.CreateUser(user);
if (result)
{
return Ok();
}
return BadRequest();
}
}
public interface IUserService
{
Task<bool> CreateUser(User user);
}
public class UserService : IUserService
{
private readonly ApplicationDbContext _context;
public UserService(ApplicationDbContext context)
{
_context = context;
}
public async Task<bool> CreateUser(User user)
{
_context.Users.Add(user);
return await _context.SaveChangesAsync() > 0;
}
}
The updated code no longer stores sensitive user information in the source code. Instead, it uses a secure data storage mechanism, a database, to store user information.
The User
class remains the same, representing the user with properties for Id
and PhoneNumber
.
The UserController
class now has a dependency on IUserService
, which is injected through the constructor. The CreateUser
method now calls the CreateUser
method of the IUserService
to store the user information in the database.
The IUserService
interface defines a contract for user services, with a CreateUser
method that takes a User
object and returns a Task<bool>
indicating the success or failure of the operation.
The UserService
class implements IUserService
, taking a dependency on ApplicationDbContext
(representing the database context) through its constructor. The CreateUser
method adds the user to the Users
DbSet and saves the changes asynchronously, returning a boolean indicating whether or not the operation was successful.
This approach ensures that sensitive user information is securely stored in the database and not in the source code. It also allows for the implementation of additional security measures such as encryption and access controls.