How Certificate Transparency enables Auditing

In the digital world, securing communications between users and websites is paramount. SSL/TLS certificates play a critical role in this process, but how can organizations ensure that these certificates are issued correctly and are not compromised? This is where Certificate Transparency (CT) comes into play, enabling more robust auditing and enhancing security.

What is Certificate Transparency?

Certificate Transparency is an open framework developed by Google that aims to monitor and audit SSL/TLS certificates. It functions by logging all certificates issued by Certificate Authorities (CAs) in publicly accessible logs. This allows anyone to inspect and verify certificates, ensuring that no unauthorized or rogue certificates are issued.

How Certificate Transparency Works

1. Logging Certificates: When a CA issues a new SSL/TLS certificate, it is logged in two or more CT logs. These logs are append-only, meaning once a certificate is added, it cannot be removed or modified.
2. Monitoring Logs: CT logs are public, so anyone can monitor them for certificates issued to their domains. This helps in detecting any unauthorized certificates promptly.

Why you need to audit your SSL/TLS certificates

Auditing your SSL/TLS certificates is crucial for maintaining the security and integrity of your online communications. Certificates can expire, be misconfigured, or even be issued without your knowledge, exposing your organization to significant risks. Regular audits help ensure compliance with security policies, prevent unauthorized certificate issuance, and protect against potential vulnerabilities that could lead to data breaches, man-in-the-middle attacks, or other security incidents. By proactively managing and auditing your certificates, you safeguard your organization’s digital trust and reputation.

How SSLBoard uses CT Logs for Auditing

The CT Log infrastructure is public, but there are billions of certificates spread across dozens of CT logs, and these logs are not searchable. That’s where SSLBoard.com shines: it scrapes all CT logs and indexes the information so that you don’t have to. Moreover, it cross references every one of your certificates with every host name they contain, and checks which certificates are actively used on your servers!

This results in the capability to audit a whole domain with subdomains, in a matter of minutes, ensuring comprehensive oversight.