How to make Firefox more secure with TLS 1.2

To increase the security of the SSL/TLS encrypted link setup by your Firefox browser enter “about:config” in the browser bar, press enter and change the following preferences:

Setting both to a value of 3 means that Firefox will only use TLS 1.2. This is currently the most secure. However TLS 1.2 may not be supported by every webserver behind the website you surf to. If you find that you can not setup a TLS 1.2 encrypted link to a website then you can try lowering the value for the security.tls.version.min preference to 2. The value 2 means that TLS 1.0 is supported as a minimum which is not as good as TLS 1.2 but better than SSLv3 (a value of 1).

If you really need to allow SSLv3 based links to a website then at least make sure that you disable security.ssl3.rsa_fips_des_ede3_sha:

It also makes sense to disable RC4 by setting the preferences below to false:

You can check how secure your SSL/TLS client is at How’s My SSL?

You can also install the CipherFox add-on in Firefox which displays the current SSL/TLS cipher and certificate chain in the Add-on bar and Site ID dialog.

Be safe out there!