Recently I’ve been looking at the security of the internet facing systems at work. It’s amazing how many bits of software by default still ship with massively insecure settings.
One of my main focusses has been IIS, and as such the related software we use that is built on top of IIS – Forefront UAG and Forefront TMG.
There is a fantastic website from Qualys that will scan an HTTPS server, check the certificate and all the various options around ciphers in use and what capabilities are/aren’t available and then give you a score based on current best practices. This is also updated quickly and takes into account things like the Poodle vulnerability.
You can visit their SSLLabs site to check the current status of this site, or check your own.
There are a number of articles on the web (and on SSLLabs above) dealing with disabling SSLv2 and SSLv3, which is great but isn’t actually sufficient, and remembering to set all of these things is quite tedious.
I was pleasantly surprised to discover a fantastic powershell script that sets all of the required registry entries for Windows servers to allow you to score an A rating.
It’s important to point out that all of the latest and greatest security options for HTTPS will actually break backwards compatability with some earlier Android handsets, and (shock!) Internet Explorer 6… I’m not going to cover off any changes required if this is important to you, because it shouldn’t be.
Anyway, hass.de has a fantastic script to fix your Windows server schannel security settings. A reboot is required to take effect.
You can read about their options and download the scripts to get your Windows servers an A rating from https://www.hass.de/content/setup-your-iis-ssl-perfect-forward-secrecy-and-tls-12. They also cover the option you can change if you want to get an A+!