What is an “SSL Handshake Failed Error” And How Do You fix It?- A Complete Guide

An SSL handshake is a process that begins when your browser sends a secure connection request to a web server. When this request is made, they share encryption algorithms, keys, and other details about their connection before finally agreeing to exchange data. This exchange of data is called an SSL handshake. 

This handshake is essential for establishing a secure connection before transferring data. The SSL handshake involves algorithm agreement, certificate exchange, and the exchange of keys using a standard algorithm. So, the ‘SSL handshake’ is the term given to a secure process that aids in the encryption of client-server communication using cryptographic keys. 

These keys are exchanged between the server and the client using one of the two shared algorithms decided upon by both the server and the client. The ‘SSL handshake failed’ error message appears if there is a fault during this process.

In a situation where the handshake fails due to the inability of the server or client to establish a connection through the protocol, the connection might be rendered insecure. This may affect your communication.

This article will teach you what can cause an unsuccessful SSL handshake and how to fix it.

Causes Of SSL Handshake Error

Summarily, “SSL Handshake Error” is a message you receive when the SSL handshake process fails. Several circumstances, however, could lead to an unsuccessful SSL handshake. These include:

• The client is using the wrong date or time.
• The hostname in the URL doesn’t match the name on the certificate.
• The certificate has expired or is no longer valid.
• The server does not support the cipher suite being requested.
• The server or the client does not support the SSL/TLS protocol.
• The client’s browser and its specific configuration are causing the error.
• A third-party intercepting the connection on the client side.

The SSL Handshake Failed error message may appear differently based on the client application or server you are attempting to interact with. In GitHub, for example, it will appear like this:

If you’re using Cloudflare, an SSL Handshake Failed error will present as a 525 error that looks like this:

How to Fix SSL Handshake Error?

Correct The Time and Date On Your Device

This is the easiest and most common fix to most SSL handshake errors. If the system time and date on your computer or device are wrong, it can impede a successful SSL Handshake. SSL certificates are time-bound; they possess finite lifespans and become invalid after a specific expiration date. 

If you check your system time and date and it’s correct, then this is not what is causing the unsuccessful SSL Handshake.

Update Your Web Browser

You must keep your Operating System and applications up to date; this includes your web browser. You may receive the SSL Handshake Failed message because your device and server do not support the same SSL version, resulting in a protocol mismatch. The solution would be to update your browser to use the latest SSL protocol.

Try Another Browser

If the SSL Handshake error persists after updating your web browser, then your browser may be causing the SSL Handshake Failed error. It could be a problem with your settings, browser plugins, or something else. In such an instance, using a different web browser would be best. 

Switch to another browser to verify if your default browser was the problem. If the handshake does not fail in your second browser, reset your default browser to its default settings and disable your plugins. It is advisable that you disable each of your plugins sequentially while testing the website to determine which plugin is causing the problem.

If the error message persists even with a different browser, the problem is not your browser configuration.

Verify your SSL certificate.

An SSL certificate with flaws can prohibit an SSL handshake from being completed. This may result in an SSL Handshake Failed error message. The handshake will most likely fail if the hostname certificate has an incorrect hostname or has passed its expiry date. As a result, it is essential that you make sure that your SSL certificate is installed correctly and renewed as required.

You can use an SSL Server Test to ensure your SSL configuration is installed, valid, and trusted.

Ensure the Cipher Suites Match

Cipher Suite mismatch is a common cause of SSL handshake errors resulting from the failure of your browser to establish a secure connection with a server that uses SSL or HTTPS. When the Cipher Suites used by a server do not support the one used by a browser, an SSL Handshake Failed error will occur.

You can use the SSL labs to check for a mismatch between your browser’s Cipher Suites and the server suites. 

Step 1: Visit SSL Labs.

Step 2: Navigate to Projects.

Step 3: Click SSL Client Test.

Step 4: Scroll down to Protocol Features, which will list which Cipher Suites your browser supports, in order of preference.

Step 5: Now, open SSL Labs in another tab, and navigate to Projects.

Step 6: Click SSL Server Test.

Step 7: Type in the domain name you are trying to visit that is resulting in the SSL Handshake Failed error.

Step 8: Scroll down to Configuration, which will list which Cipher Suites the server supports in order of preference.

If you verify that your browser and server use the same Cipher Suite, there is no mismatch.

Conclusion

This article discusses some of the most effective remedies for the SSL handshake issue, which may occur due to browser or system settings. In most cases, adjusting the time and date settings or removing the troublesome browser extensions resolves the issue.

For server-related concerns, only the website owner or administrator can fix the ‘SSL handshake failed’ problem. Only the website proprietor or administrator can resolve the ‘SSL handshake failed’ error on the server. Typical server-side issues include invalid SSL certificates, cipher suite difficulties, and installation of incorrect SSL certificates. In such a situation, it is recommended that you contact the website’s owner or administrator to resolve the issue.