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What is a Trust Store and the Issues Associated with It

Secure communication is essential in today’s world, and Trust stores play an important role in ensuring this. A trust store is a digital repository that stores certificates from verified sources.

When we visit a website and see a secure lock icon, it’s a sign that we are connected to a secure network. It’s because a complex system works behind the scenes. A trust store makes this system possible. But what exactly is a trust store, and how does it function?

Think of our friends on social media as a trust store. We only accept a friend request from someone we know or recommended by a trusted connection. Likewise, a trust store is a repository that holds onto digital certificates issued by the Certification Authority (CA) that our operating system or browser trusts. These certificates are like digital identification of the websites we visit and tell us whether the website is trustworthy or not.

Now, to get a better understanding, let us understand how the process of verification works:

  1. Websites send digital certificates

    When we visit a website, it sends a digital certificate to the browser.

  2. Trust Store Checks the Certificate

    The Trust store comes into play here; it verifies the digital certificate.

  3. Is the certificate trustworthy?

    If any CA signs the digital certificate on the trust store list, then the certificate is deemed trustworthy and hence the connection is secure.

  4. Connection is Not Secure

    However, if the certificate doesn’t match a known CA, the trust store throws up a red flag. This is when we see the “connection not secure” message.

Now, Operating systems and web browsers maintain a list of these certificates called trust stores. This helps implement strict criteria to determine which CA certificates are deemed trustworthy. Trust stores enable secure communication by referencing these certificates during any online interaction and help you avoid connecting with potentially malicious entities. 

To see trusted root certificates on your Windows machines, follow these steps:

  1. Open Control Panel. 
  2. Click on “Network and Internet”. 
  3. Select “Internet Options”.
  4. In the Internet Properties window, go to the “Content” tab. 
  5. Click on the “Certificates” button.
  6. In the Certificates window, move to the “Trusted Root Certification Authorities” tab.
Microsoft Root Certificate Purpose

So now the question arises where this trust store comes from. There are four major organizations that maintain such trust stores.

  1. Microsoft root certificate program that is used by Windows. 
  2. Apple root certificate program is used by all Mac devices. 
  3. The Mozilla root certificate program is used by Mozilla itself and most Linux distributions. 
  4. Google root certificate program used by google chrome and other applications. 

Each of these entities has its standards and requirements for including a Root certificate in its trust store, but they all require a CA to undergo one or more audits before their Root certificate can be included.

Now, there are hundreds of CAs that are trusted by the CA/Browser Forum Baseline Requirements, which sets the rules that the trusted certificate authorities (CAs) are supposed to follow before issuing certificates.

Moreover, CAs are audited for compliance checks with these rules and protocols as part of the WebTrust audit program, which is required by some root certificate programs like Mozilla for inclusion in their trust stores.

The following table provides a breakdown of key aspects of the trust store. 

Aspect Description Example
Number of Trusted Root CAs The number of Certificate Authorities (CAs) whose certificates are pre-installed and trusted by a specific trust store.
  • Windows 10 typically trusts around 100-150 Root CAs.
  • Mozilla Firefox uses a more selective approach, trusting around 50-60 Root CAs.
Frequency of Updates How often the trust store is updated with new or revoked certificates? Trust stores are updated on a weekly or monthly basis.
Types of Certificates Stored The different types of certificates a trust store might contain, beyond just website certificates.
  • Website certificates(SSL/TLS)
  • Code signing certificates (used to verify the authenticity of software)
  • Email signing certificates (used to digitally sign emails)
Common Verification Errors Examples of errors a user might encounter if a website’s certificate doesn’t validate against the trust store.
  • Certificate Not Valid” – This is a warning about an expired certificate or one issued by an unknown CA.
  • “Connection Not Secure” – This is a general warning that the website’s certificate couldn’t be validated.

In this scenario, certificate authorities are considered trustworthy third parties when issuing digital security certificates like SSL, code signing, etc. They handle public keys and other encryption-related credentials. They also authenticate and associate websites, email addresses, businesses, and others with cryptographic keys.

The CA is responsible for verifying and issuing the organization’s data with distinctive certificates. These CAs are trusted to verify a website’s / organization’s legitimacy, and some researchers have pointed out that their role in this overall system could be a single point of failure. Moreover, if a CA is compromised, this essentially means that, theoretically, any attacker could issue fake certificates and exploit the trust store verification process. 

Now, managing the intricate web of keys and certificates can be complex. Security researchers highlight this complexity as a potential vulnerability. Any errors or vulnerabilities in this process could create opportunities for attackers to exploit. 

In order to resolve these issues, intricate solutions are generally in place, such as a certificate lifecycle management solution (CLM). A CLM could potentially help an organization manage its certificates.

Implementing a centralized CLM allows for better and centralized oversight and control over the entire certificate lifecycle. It helps the organization have better visibility of certificates, enforces standardized processes, tracks certificate usage, and promptly identifies and addresses any issues.  


In Conclusion, Trust stores play a crucial role in establishing a secure connection for any online interaction. They are like a secure vault that stores certificates from verified sources (Certification Authorities). This vault is used to verify a website’s identity. The process is like a digital handshake with confirmed credentials to ensure a secure and encrypted connection.

However, we must acknowledge that this process has inherent complexities. The high dependency on CA creates the potential for a single point of failure. Additionally, managing the web keys and certificates can create complexity and lead to vulnerabilities.

Moreover, to overcome these challenges, our CLM CertSecure could help manage these certificates and potentially solve the issues with oversight and complexities.

How can Encryption Consulting help? 

Encryption Consulting provides specialized services tailored to identify vulnerabilities and mitigate risks by providing PKI Services. Our strategic guidance aligns PKI solutions with organizational objectives, enhancing efficiency and minimizing costs. By partnering with Encryption Consulting, organizations can unlock the full potential of PKI solutions, realizing tangible financial benefits while maintaining robust security measures. 

CertSecure Manager has a comprehensive suite of lifecycle management features. From discovery and inventory to issuance, deployment, renewal, revocation, and reporting. CertSecure provides an all-encompassing solution. Intelligent report generation, alerting, automation, automatic deployment onto servers, and certificate enrollment add layers of sophistication, making it a versatile and intelligent asset. 

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About the Author

Divyansh is a Consultant at Encryption Consulting, specializing in Public Key Infrastructures (PKIs) and cloud applications. With extensive experience developing software applications, he is adept at working with clients to develop specialized solutions. His expertise in PKIs and certificate lifecycle management enables him to develop Encryption Consulting's CLM solution, adding a valuable dimension to his skill set. His work with clients has ensured they achieve the best possible outcomes with encryption regulations and PKI infrastructure design.

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