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Authentication mechanism absence or evasion

Need​

Implementation of a robust and secure authentication mechanism

Context​

  • Usage of Go 1.16 for developing high-performance and concurrent applications
  • Usage of Gin framework for building web applications in Go

Description​

Non compliant code​

package main

import (
	"github.com/gin-gonic/gin"
)

func main() {
	r := gin.Default()

	r.GET("/protected", func(c *gin.Context) {
		c.JSON(200, gin.H{
			"message": "You accessed protected data without authentication",
		})
	})

	r.Run() // listen and serve on 0.0.0.0:8080
}

This is a simple Go application using the Gin framework. It starts a server and listens on the port 8080 for incoming connections. The server has a single route (/protected) that returns a JSON response with a message.

The problem here is that there is no authentication mechanism in place to protect the /protected route. Any client can send a GET request to this endpoint and receive the protected data without needing to provide any form of identification or credentials.

This represents a major security vulnerability as it allows unauthorized access to sensitive information. In a real-world application, this could include user data, confidential business information, etc.

An attacker could potentially exploit this vulnerability to access and manipulate protected resources, leading to data breaches, unauthorized actions, and other potentially serious consequences.

To fix this vulnerability, an authentication mechanism needs to be implemented. This could be in the form of a simple username/password combination, a token-based system like JWT (JSON Web Token), or any other secure method that ensures only authorized users can access protected resources.

Steps​

  • Implement a robust authentication mechanism.
  • Ensure that all sensitive resources are protected and can only be accessed by authenticated users.
  • Use secure session management techniques to maintain user sessions.
  • Implement proper access control mechanisms to restrict unauthorized access to protected resources.
  • Consider using industry-standard authentication protocols such as OAuth or JWT for secure authentication and authorization.
  • Regularly update and patch the authentication mechanism to address any security vulnerabilities.
  • Perform thorough security testing and code reviews to identify and fix any potential authentication bypass vulnerabilities.

Compliant code​

package main

import (
	"github.com/gin-gonic/gin"
	"github.com/gin-contrib/sessions"
	"github.com/gin-contrib/sessions/cookie"
)

func main() {
	r := gin.Default()

	// Set up a secure cookie-based session store
	store := cookie.NewStore([]byte("secret"))
	r.Use(sessions.Sessions("mysession", store))

	r.GET("/protected", func(c *gin.Context) {
		session := sessions.Default(c)
		user := session.Get("user")
		if user == nil {
			c.JSON(401, gin.H{"error": "Unauthorized"})
			return
		}

		c.JSON(200, gin.H{
			"message": "You accessed protected data with authentication",
		})
	})

	r.Run() // listen and serve on 0.0.0.0:8080
}

The updated code now includes an authentication mechanism using secure cookie-based sessions. The github.com/gin-contrib/sessions package is used to manage sessions in the Gin framework.

A new session store is created using a secret key and the Sessions middleware is added to the Gin engine. This middleware will load the session data for each request.

In the handler for the /protected route, the session data is retrieved and the user is checked. If the user is not authenticated (i.e., there is no user data in the session), a 401 Unauthorized response is returned. If the user is authenticated, the protected data is returned as before.

This ensures that only authenticated users can access the protected data, and unauthorized access attempts will be blocked.

Please note that this is a basic example and in a real-world application, you would typically have a login route where users can authenticate and their user data is stored in the session. Also, the secret key used for the session store should be kept secure and not hardcoded as in this example.

References​

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