Wildcard SSL: One Certificate for all Subdomains

Fast and Cost-Effective Solution to Secure Unlimited Subdomains

Wildcard SSL allows you to protect an unlimited number of subdomains in a single certificate. This is ideal for anyone running or managing multiple websites or pages of the same domain. The initial fee typically includes additional subdomains that you can add in the future.

Whereas traditional SSL certificates, which provide only the appropriate domain name (e.g., www.yourdomain.com), can only be used to protect the same domain name, Wildcard SSL certificate which expressed on *.your domain.com is able to protect all possible subdomains.

Wildcard SSL provides complete subdomain encryption, making it a simple and convenient solution for most websites. It is only available in Domain Validated (DV) and Organized Validated (OV).

While a website’s administration using a Wildcard SSL is efficient, they pose a system security risk to the server. Thus, if this is your choice, you are encouraged to use advanced features such as SSL check and other security measures when deploying Wildcard SSL.

Reasons to Choose Wildcard SSL

1. Cost savings

Purchasing separate SSL certificates for each of your subdomains will be expensive. Wildcard SSL universally protects an unlimited number of subdomains per certificate. Whether you have 50, 100, 500 or even more, there are no extra and hidden costs. Thus, a Wildcard SSL can save hundreds of dollars.

2. Easy certificate management

As the company grows, it will have new subdomains for each new department, product lines and facilities. Once you have purchased a new SSL certificate, you must go through the entire inspection and installation process of the certificate signing request (CSR) generation. In addition, each SSL certificate has a different renewal date to make your tracking system more powerful. Imagine how much the costs will accumulate.

A Wildcard SSL certificate may contain an unlimited number of subdomains in the same certificate. In addition, you can add a subdomain at any time, even in the middle of the validation period! Therefore, you can add an unlimited number of subdomains at any time. A SSL Wildcard certificate is conveniently used and managed through the same authentication process, same installation and renewal date.

3. Multiple Servers Flexibility

A Wildcard SSL certificate might be installed on multiple web servers. With most companies, there are often different departments handling different subdomains (e.g. companies often host dev.domain.com and test.domain.com in the IT department).
In addition, there are also separate subdomains for resellers, suppliers, resellers, HR departments, international teams and various product lines.

To make operations easier, companies often host these subdomains on different web servers. The same Wildcard SSL certificate can be installed on those different servers. The one thing left to do is as simple as moving your private key to the secondary server. You don’t need to buy individual SSL certificates for numerous servers.

Installing Wildcard SSL certificates on multiple servers may entail additional fees. While some certificate authorities (CAs) do not allow the use of a Wildcard SSL on many website servers, others give unlimited server licenses.

The Risks of Using Wildcard Certificates

Wildcard SSL certificates have many disadvantages;

1. They are not available at all levels of authentication. You can get wildcards at Domain Verification (DV) and Organization Verification (OV), but not Extended Verification (EV). This means that if you want to use an EV certificate on a subdomain, you must use a single certificate or multi-group certificates.
2. There is a common misconception that Wildcards SSL make all subdomains safe. This is only partially true. These certificates protect all subdomains at the specified URL level. There are several levels of subdomain. This increases the complexity. It is much more difficult to deploy Wildcards in the second- and third-levels. The best option is to use a multi-domain SSL certificate in this case.
3. The more domains and subdomains you have a key pair installed on, the more risks you will face. If one of the domains or subdomains is compromised, any hacker or malware can easily get to all the other subdomains. This is a reduction in SSL/TLS.
4. If a key is jeopardized on a domain or subdomain, all other subdomains and domains you have are also compromised. This can make your problems even worse.

So, yes, Wild card certificates are less secure because of their advantages.

Using Wildcard Certificates Securely

Here are some tips for using Wildcards SSL certificate for your web servers:

1. Protect your private key by all means. It’s always a necessary step for any SSL certificate, but it is a must for Wildcard SSL even more
2. If possible, using other SSL certificate instead of Wildcard SSL
3. If you still need to use it, try to use it for the lowest level subdomains and do not use it for root level domains

4. Ensure that you implement all possible certificate revocation features which you have at your disposal such as SSL check

5. A relatively new popular approach is the use of short-term certificates

But ultimately, the use of Wildcard certificates depends on your being satisfied with the benefits they bring over the risks.

The bottom line is that no one wants the name of the organization involved in a phishing attack. This damages the reputation and the credibility of a brand. Consequently, making it as difficult as possible for cybercriminals to infiltrate your domain and tamper with your encryption is imperative. It increases the burden of issuing and maintaining certificates for a particular server, but with the right operating platform, you can reduce risk and raise awareness through automation and intelligence.

The use of Wildcard SSL certificates in production systems should therefore be avoided. Use a frequently rotated certificate for specific subdomains instead. A compromised Wildcard certificate can have serious consequences. However, you can prevent (or at least reduce) the potential impact of an attack by using a short-term, non-Wildcard certificate.