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Insecure encryption algorithm - SSL/TLS

Need

Implementation of secure encryption algorithms for SSL/TLS communication

Context

  • Usage of Ruby for building dynamic and object-oriented applications
  • Usage of net/http for building HTTP servers in a Node.js application

Description

Non compliant code

require 'net/http'
uri = URI('https://example.com')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true
http.ssl_version = :SSLv3
request = Net::HTTP::Get.new(uri.request_uri)
response = http.request(request)

The above code is a Ruby script that creates an HTTPS request to the 'example.com' website.

The vulnerability lies in the line where http.ssl_version = :SSLv3 is set. SSLv3 is an outdated and insecure version of the SSL protocol, which has been deprecated due to a number of serious vulnerabilities, including the POODLE (Padding Oracle On Downgraded Legacy Encryption) attack.

In this code, the usage of SSLv3 makes the communication between the client and the server susceptible to these vulnerabilities, potentially allowing an attacker to decrypt sensitive information.

Steps

  • Update the SSL/TLS protocol version to a secure version.
  • Remove the usage of SSLv3 and use a more secure protocol version such as TLSv1.2 or TLSv1.3.
  • Ensure that the server supports the chosen secure protocol version.
  • Verify that the SSL/TLS certificate used by the server is valid and trusted.
  • Consider using a secure library or framework that handles SSL/TLS connections securely.

Compliant code

require 'net/http'
uri = URI('https://example.com')
http = Net::HTTP.new(uri.host, uri.port)
http.use_ssl = true
http.ssl_version = :TLSv1_2
request = Net::HTTP::Get.new(uri.request_uri)
response = http.request(request)

The original code was using an insecure SSLv3 protocol for the SSL/TLS connection. This protocol version is known to have several vulnerabilities and is considered insecure. The updated code uses the TLSv1.2 protocol, which is currently considered secure.

The http.ssl_version = :TLSv1_2 line sets the SSL/TLS protocol version to TLSv1.2. This ensures that the connection will be encrypted using this secure protocol version.

It's important to note that the server must support the chosen protocol version. If the server doesn't support TLSv1.2, the connection will fail. Therefore, it's necessary to ensure that the server supports this protocol version.

Additionally, it's crucial to verify that the SSL/TLS certificate used by the server is valid and trusted. This is not shown in the code, but it's an important part of a secure SSL/TLS connection.

Finally, consider using a secure library or framework that handles SSL/TLS connections securely. This can help to avoid potential security issues and vulnerabilities.

References