Privilege escalation - Scala

Need

Enhancement of role-based access control and privilege management

Context

1. Usage of Scala for building scalable and high-performance applications
2. Usage of Play Framework's MVC module for handling HTTP requests and responses
3. Usage of Scala's global execution context for concurrent programming

Description

Insecure Code Example

import play.api.mvc._
import scala.concurrent.ExecutionContext.Implicits.global

class AdminController @Inject()(val controllerComponents: ControllerComponents) extends BaseController {

  def adminAction = Action.async { implicit request: Request[AnyContent] =>
    val userRole = request.session.get("role")
    userRole match {
      case Some("admin") => {
        // Perform admin operations
      }
      case _ => {
        // Redirect to login or unauthorized page
      }
    }
  }
}

In the above code, the `AdminController` is used to handle requests that should be restricted to users with administrative privileges. The `adminAction` function checks the user's role from the session and allows the operation to proceed if the user is an admin. However, this code is insecure because it trusts the user role value stored in the session. An attacker could manipulate the session data and set the "role" to "admin", thus escalating their privileges and gaining administrative access. The vulnerability lies in the fact that the application does not verify if the user actually has the role they claim to have. It simply trusts the role value from the session. This is a classic example of a Privilege Escalation vulnerability where a standard user can obtain administrative access due to insecure role configuration.

Steps

1. Review the role configuration to ensure that it is properly secured.
2. Implement proper authentication and authorization mechanisms to validate user roles.
3. Use a secure session management mechanism to store and retrieve user roles.
4. Ensure that only authorized users with the 'admin' role can access the adminAction method.
5. Implement proper error handling and redirect unauthorized users to a login or unauthorized page.
6. Regularly review and update the role configuration to prevent any potential privilege escalation vulnerabilities.

Secure Code Example

import play.api.mvc._
import scala.concurrent.ExecutionContext.Implicits.global

class AdminController @Inject()(val controllerComponents: ControllerComponents, authService: AuthService) extends BaseController {

  def adminAction = Action.async { implicit request: Request[AnyContent] =>
    val userRole = request.session.get("role")
    authService.authenticate(userRole) match {
      case true => {
        // Perform admin operations
      }
      case false => {
        // Redirect to login or unauthorized page
      }
    }
  }
}

class AuthService {
  def authenticate(userRole: Option[String]): Boolean = {
    userRole match {
      case Some("admin") => true
      case _ => false
    }
  }
}

The updated code includes an `AuthService` class that is responsible for authenticating the user role. This service is injected into the `AdminController` and used to authenticate the user role before performing any admin operations. In the `adminAction` method, the `AuthService`'s `authenticate` method is called with the user role retrieved from the session. If the user role is 'admin', the `authenticate` method returns `true` and the admin operations are performed. If the user role is not 'admin', the `authenticate` method returns `false` and the user is redirected to a login or unauthorized page. This approach ensures that only users with the 'admin' role can access the `adminAction` method, preventing privilege escalation vulnerabilities. It also separates the concerns of authentication and controller logic, making the code easier to maintain and test. Remember to always use secure session management mechanisms to store and retrieve user roles, and regularly review and update the role configuration to prevent any potential privilege escalation vulnerabilities.

References

Last updated

2023/09/18