Disabling Outdated Versions of SSL/TLS
How to disable outdated versions of SSL/TLS in Apache
In order to provide the most robust security possible, old versions of SSL/TLS should be disabled. Most modern browsers support the newer and more secure versions of SSL/TLS so disabling the less secure and older versions of SSL/TLS should not hinder user experience.
To disable outdated versions of SSL/TLS in Apache:
- On your server, edit ssl.conf (usually located in /etc/httpd/conf.d).
- Find the line that begins with the following in the file: SSLProtocol all -SSLv2
- Comment out the line by adding a # before the line. This will disable TLS 1.0/1.1 and SSL 2.0/3.0.
- Add the following line underneath the line you have just commented out: SSLProtocol all -SSLv2 -SSLv3 -TLSv1 -TLSv1.1
- Next, find the line that begins with the following in the file: SSLCipherSuite HIGH:MEDIUM:!aNULL:!MD5:!SEED:!IDEA
- Comment out the line by adding a # before the line.
- Add the following line underneath the line you have just commented out: SSLCipherSuite HIGH:!aNULL:!MD5:!3DES
- This ensures the use of SSL encryption only with a high degree of protection.
- Add the following line underneath the line you just added: SSLHonorCipherOrder on
- This ensures that server cipher preferences are used and not the client preferences.
- Save and close the file.
- Restart the Apache service with the following command: service httpd restart
- NOTE: This command will differ depending on your OS.
Be sure to test all applications that interact with your server. If you experience any problems, you can remove the comments (#) and added lines to return to the previous version of the file.
Article ID: 870
Created On: Thu, Aug 6, 2020 at 10:06 AM
Last Updated On: Thu, Aug 6, 2020 at 10:54 AM
Authored by: rspielman
Online URL: https://support.nagios.com/kb/article/disabling-outdated-versions-of-ssl-tls-870.html