Automatic information enumeration

Need

Prevention of automatic information enumeration

Context

• Usage of Go 1.16 for developing high-performance and efficient applications
• Usage of Gin for building web applications in Go
• Usage of net/http for handling HTTP requests and responses in a Node.js server

Description

Non compliant code

package main

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

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

	router.GET("/system_info", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{
			"openPorts":     "22, 80, 443",
			"availableServices": "HTTP, HTTPS, SSH",
			"usersData":     "User1: [email protected], User2: [email protected]",
		})
	})

	router.Run(":8080")
}

The above code is a simple Go backend application using the Gin framework. It has a single endpoint /system_info that responds with a JSON object containing information about the system.

The vulnerability lies in the /system_info endpoint. This endpoint exposes sensitive system information like open ports, available services, and users' personal data. This information can be used by an attacker to understand the system's structure and plan an attack.

The open ports ("22, 80, 443") indicate which network ports are accepting connections, which can be exploited to gain unauthorized access to the system or perform a denial of service attack.

The available services ("HTTP, HTTPS, SSH") reveal the protocols that the system is using, which can be used to identify potential vulnerabilities within these services.

The users' personal data ("User1: [email protected], User2: [email protected]") is a privacy concern, as it can be used for phishing attacks or identity theft.

This endpoint should not be publicly accessible and should be protected with appropriate authentication and authorization mechanisms. Additionally, sensitive information like this should never be exposed, even to authenticated users.

Steps

• Remove the endpoint '/system_info' that exposes system information.
• Review the codebase for any other endpoints or functions that expose sensitive information and remove or secure them.
• Implement proper access controls and authentication mechanisms to restrict access to sensitive information.
• Regularly update and patch the application and its dependencies to address any known vulnerabilities.
• Implement input validation and sanitization to prevent any unauthorized access or injection attacks.
• Implement logging and monitoring mechanisms to detect and respond to any suspicious activities or unauthorized access attempts.

Compliant code

package main

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

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

	router.Run(":8080")
}

The original code had a vulnerability where it exposed sensitive system information such as open ports, available services, and user data. This information could be used by an attacker to gain unauthorized access to the system or to launch further attacks.

The fixed code removes the '/system_info' endpoint that was exposing this sensitive information. This is the first and most direct step in mitigating the vulnerability.

However, fixing this specific piece of code is not enough to secure the application. Here are some additional steps that should be taken:

• Review the entire codebase for any other endpoints or functions that may be exposing sensitive information and remove or secure them.
• Implement proper access controls and authentication mechanisms to restrict access to sensitive information. This could include things like requiring a valid user session for any request that accesses sensitive information, or implementing role-based access controls to limit what different users can do.
• Regularly update and patch the application and its dependencies to address any known vulnerabilities. This is a crucial part of maintaining security, as new vulnerabilities are discovered and patched regularly.
• Implement input validation and sanitization to prevent any unauthorized access or injection attacks. This can help to ensure that only valid, expected data is processed by the application.
• Implement logging and monitoring mechanisms to detect and respond to any suspicious activities or unauthorized access attempts. This can help to identify potential security incidents quickly, allowing for a faster response.

By following these steps, you can significantly improve the security of your application and protect it from common vulnerabilities and attacks.

References

• 047.Automatic information enumeration