Have you seen the following error?
Secure Connection Failed
An error occurred during a connection to example.com. SSL received a weak ephemeral Diffie-Hellman key in Server Key Exchange handshake message. (Error code: ssl_error_weak_server_ephemeral_dh_key)
The page you are trying to view cannot be shown because then authenticity of the received data could not be verified.
Please contact the website owners to inform them of this problem.
You get this error when the server you are trying to connect to is vulnerable to the logjam vulnerability. You should report this problem to the server owner so they can fix it immediately. This server is considered unsafe and is vulnerable to man-in-the-middle attacks.
Newer versions of Firefox and Chrome will block connections to unsafe servers by default.
Bypassing the weak security
If you really wish to access the site anyway you can go to
about:config in the address bar of Firefox. Then search for
security.ssl3.dhe. Then change this value to false.
After that, your page should load. Please change the setting in your browser back to true when you are done so your browser is not vulnerable to logjam and man-in-the-middle attacks.