Co-founder of Radical Prime and Enigma Bridge. Indendent consultant on security and encryption systems (incl. large banking, payment, and enterprise systems) ... and a university professor.
Looking back, we can find many examples of errors in the algorithms used to create encryption keys. Not very many of them, however, were found in chips designed and sold as high-security devices for email signing, verifying software integrity, VPN access, or citizen e-ID cards.
As I was collecting reliability data for several PKI systems, I included Let’s Encrypt as it’s by far the biggest PKI system I was aware of. It provides its status data and its history at https://letsencrypt.status.io and here’s my informal analysis of its production systems.
This is an interesting one. The first impulse is to simply answer NO, you can’t do it, that’s the point of HTTPS. But it’s all about networking and one can do quite some magic with proxies, forwarding, and the SNI extension in TLS protocols.
We have compiled all practical information we could find and written it up at Numbers you need to know. It’s a long list of restrictions, rate limits, and other useful information to keep in mind. Here’s a few selected points that we found interesting. Big thanks to schoen from Certbot/EFF for pointing out numerous inaccuracies.
A team of great people from the Security Group at UCL and our start-up Enigma Bridge designed and implemented a practical security system tolerant to severe attacks compromising all parts of the supply chain. We will present and demonstrate it at DEFCON in Las Vegas.
Is it really possible to design an encryption system, which is as strong as its strongest link? There is never a straight “yes” answer to this question, but we are now as close as one can get.
We have all heard about hackers stealing huge user databases with passwords as they are tempting bounties. FT, Guardian and many others create a new kind of reward – their internet encryption keys via CDNs – services speeding up web traffic.
We have started testing our SSL certificate spot checks – KeyChest – and realized that we were conceptually different from SSL Labs. We focus on the server rather than the domain name and it makes a difference.
While implementing features of the certificate planner, we have added a few handy features to the KeyChest spot checker as well. It is now much more than just a tool to check when a website certificate expires.