Skip to main content

Insecure functionality - Fingerprint

Need​

Secure and controlled user data updates

Context​

  • Usage of Scala for building scalable and functional applications
  • Usage of play.api.mvc for handling HTTP requests in Play Framework

Description​

Non compliant code​

import play.api.mvc._

object UserController extends Controller {

  def updateUser = Action { request =>
    val body: AnyContent = request.body
    val jsonBody: Option[JsValue] = body.asJson

    // Expecting json body: {"name":"foo", "email":"[email protected]", "fingerprint":"123456"}
    jsonBody.map { json =>
      val name = (json \\ "name").as[String]
      val email = (json \\ "email").as[String]
      val fingerprint = (json \\ "fingerprint").as[String]
      
      // Update user information
      User.update(name, email, fingerprint)
      
      Ok("User updated.")
    }.getOrElse {
      BadRequest("Expecting application/json request body")
    }
  }
}

The above Scala code represents a Play Framework controller action that is used to update user information. The updateUser action is expecting a JSON request body with three parameters: name, email, and fingerprint.

The vulnerability lies in the fact that there is no authentication or authorization check before updating the user data. This means that any user, authenticated or not, can send a POST request to this endpoint with a JSON body and the server will update the user information based on the provided fingerprint.

An attacker can exploit this vulnerability by sending unsolicited POST requests with different fingerprint values and corresponding user data. This would result in updating the information of users without their consent or knowledge. This is a serious security issue as it directly affects the integrity and confidentiality of user data.

Furthermore, the application does not validate the fingerprint value before using it to update the user information. This could potentially lead to other security issues such as SQL Injection if the fingerprint value is used in a SQL query without proper sanitization.

Steps​

  • Implement authentication and authorization mechanisms to ensure that only authorized users can update user data.
  • Validate the user's fingerprint to ensure it is a valid and secure value.
  • Use a secure method to update user information, such as parameterized queries or prepared statements, to prevent SQL injection attacks.
  • Sanitize and validate the input data to prevent any potential security vulnerabilities.
  • Implement input validation to ensure that the request body contains the expected JSON structure and required fields.
  • Use a secure communication protocol, such as HTTPS, to protect the data transmitted between the client and the server.
  • Regularly update and patch the Play framework and its dependencies to ensure that any known vulnerabilities are addressed.
  • Perform security testing and code reviews to identify and fix any other potential security vulnerabilities in the application.

Compliant code​

import play.api.mvc._
import play.api.libs.json._

object UserController extends Controller {

  def updateUser = Action { request =>
    val body: AnyContent = request.body
    val jsonBody: Option[JsValue] = body.asJson

    // Expecting json body: {"name":"foo", "email":"[email protected]", "fingerprint":"123456"}
    jsonBody.map { json =>
      val name = (json \\ "name").asOpt[String]
      val email = (json \\ "email").asOpt[String]
      val fingerprint = (json \\ "fingerprint").asOpt[String]

      (name, email, fingerprint) match {
        case (Some(n), Some(e), Some(f)) if User.isValidFingerprint(f) =>
          // Update user information
          User.update(n, e, f)
          Ok("User updated.")
        case _ =>
          BadRequest("Invalid request data")
      }
    }.getOrElse {
      BadRequest("Expecting application/json request body")
    }
  }
}

The updated code now includes a validation check for the user's fingerprint. This is done by calling the User.isValidFingerprint(f) method, which should return true if the fingerprint is valid and false otherwise. This method should be implemented in the User object.

The name, email, and fingerprint are now extracted as Option[String] using the asOpt[String] method. This ensures that if any of these fields are missing from the JSON body, the application will not throw an exception but instead will return a BadRequest response.

The User.update(n, e, f) method should use a secure method to update user information, such as parameterized queries or prepared statements, to prevent SQL injection attacks.

The application should also implement authentication and authorization mechanisms to ensure that only authorized users can update user data. This could be done using middleware or by checking the user's credentials in the updateUser action.

The application should use a secure communication protocol, such as HTTPS, to protect the data transmitted between the client and the server.

Finally, the Play framework and its dependencies should be regularly updated and patched to ensure that any known vulnerabilities are addressed. Regular security testing and code reviews should also be performed to identify and fix any other potential security vulnerabilities in the application.

References​

Last updated on