Trust but Verify: A Comprehensive Analysis of CA Trustworthiness Across 5 Billion Certificates
In the vast expanse of the internet, security and trust are paramount. A critical component of maintaining this trust is the Certificate Authority (CA). Splunk, in a recent blog post, explored the idea of trustworthiness concerning CAs, evaluating over 5 billion certificates to do so. Let’s delve deeper into this study and what its findings mean for internet security and trust.
Understanding Certificate Authorities (CAs)
At the crux of secure internet connections are SSL/TLS certificates, which authenticate and secure data in transit. CAs are entrusted with the issuance of these certificates. When a CA issues a certificate to a website, it is essentially vouching for its legitimacy.
However, trust isn’t granted blindly. The question arises: how do we know that these CAs are trustworthy themselves? Splunk sought to answer this question by examining the world of CAs through the lens of data science.
Data-Driven Analysis of Trustworthiness
The Splunk team began by collecting SSL/TLS certificates from internet-wide scans. Over 5 billion certificates were analyzed, making it one of the most extensive studies of its kind. This evaluation offered insights into certificate expiration dates, top-level domains (TLDs), and the CAs that issued them.
The data unveiled a picture of the current state of the internet’s certificate ecosystem, its credibility, and areas where trust may be put at risk.
Key Findings
The study found significant variation in certificate lifetimes, both within and among different CAs. For instance, the average lifetime of certificates issued by CAs varies from 14 months to over 80 months. This disparity points towards the lack of uniform policies across different CAs and may impact the overall security of the web.
Next, the study considered the TLDs to which these certificates were issued. The most certificates were issued for .com, .net, and .org domains. However, when adjusting for the number of domains within each TLD, it was found that newer TLDs like .app, .dev, and .page had a higher certificate density. These newer TLDs are also more likely to have their sites secured by HTTPS by default.
The Trustworthiness of CAs: No Unconditional Trust
While the data provides insights, it’s essential to remember that trust cannot be unconditionally earned; it must be continually maintained. The trustworthiness of a CA is not static; it changes over time based on its actions and policies. The study highlighted some concerning findings — the average validity period of a certificate has increased over time, and certain CAs have issued certificates with validity periods of over 20 years.
These findings indicate potential risks. Longer certificate lifetimes can pose security threats, as they provide a wider window for potential cyberattacks. Also, the validity of certificates is only as good as the CAs that issue them, making the trustworthiness of CAs critical.
Conclusion: Towards a More Secure Future
The findings from the Splunk study underline the importance of understanding the trustworthiness of CAs and the potential security risks inherent in the current system. They also highlight the need for continuous scrutiny of CAs, stronger regulations, and the development of best practices that can guide the issuance and lifecycle of certificates.
In the ever-evolving landscape of internet security, data-driven studies such as this are crucial in identifying potential vulnerabilities and improving security measures. Trust in the digital world is not a given; it’s a continuous effort that involves the cooperation of multiple stakeholders, from CAs to website owners, to individual users. By analyzing and understanding the current state of internet security, we take one step closer to a safer and more secure digital future
