Edge EV UI Requires SmartScreen

A user recently noticed that when loading Paypal.com in Microsoft Edge, the UI shown was the default HTTPS UI (a gray lock): Instead of the fancier “green” UI shown for servers that present Extended Validation (EV) certificates: The user observed this on some Windows 10 machines but not others. The variable that differed between those machines wasContinue reading “Edge EV UI Requires SmartScreen”

Building your .APP website with NameCheap and GitHub Pages–A Visual Guide

I recently bought a few new domain names under the brand new .app top-level-domain (TLD). The .app TLD is awesome because it’s on the HSTSPreload list, meaning that browsers will automatically use only HTTPS for every request on every domain under .app, keeping connections secure and improving performance. I’m not doing anything terribly exciting withContinue reading “Building your .APP website with NameCheap and GitHub Pages–A Visual Guide”

Fight Phish with Facebook (and Certificate Transparency)

As of April 30th, Chrome now requires that all certificates issued by a public certificate authority be logged in multiple public Certificate Transparency (CT) logs, ensuring that anyone can audit all certificates that have been issued. CT logs allow site owners and security researchers to much more easily detect if a sloppy or compromised Certificate Authority hasContinue reading “Fight Phish with Facebook (and Certificate Transparency)”

SSLVersionMin Policy returns to Chrome 66

Chrome 66, releasing to stable this week, again supports the SSLVersionMin policy that enables administrators to control the minimum version of TLS that Chrome is willing to negotiate with a server. If this policy is in effect and configured to permit, say, only TLS/1.2+ connections, attempting to connect to a site that only supports TLS/1.0Continue reading “SSLVersionMin Policy returns to Chrome 66”

HSTS Preload and Subdomains

In order to be eligible for the HSTS Preload list, your site must usually serve a Strict-Transport-Security header with a includeSubdomains directive. Unfortunately, some sites do not follow the best practices recommended and instead just set a one-year preload header with includeSubdomains and then immediately request addition to the HSTS Preload list. The result is that any problemsContinue reading “HSTS Preload and Subdomains”

NET::ERR_CERT_INVALID error

Some users report that after updating their Operating System or Chrome browser to a more recent version, they have problems accessing some sites (often internal sites with self-signed certificates) and the browser shows an error of NET::ERR_CERT_INVALID. NET::ERR_CERT_INVALID means that a certificate was itself is so malformed that it’s not accepted at all– sometimes rejected byContinue reading “NET::ERR_CERT_INVALID error”

Understanding the Limitations of HTTPS

A colleague recently forwarded me an article about the hazards of browsing on public WiFi with the question: “Doesn’t HTTPS fix this?” And the answer is, “Yes, generally.” As with most interesting questions, however, the complete answer is a bit more complicated. HTTPS is a powerful technology for helping secure the web; all websites should beContinue reading “Understanding the Limitations of HTTPS”

Strict-Transport-Security for *.dev, *.app and more

Some web developers host their pre-production development sites by configuring their DNS such that hostnames ending in .dev point to local servers. Such configurations were not meaningfully impacted when .dev became an official Generic Top Level Domain a few years back, because even as smart people warned that developers should stop squatting on it, Google (the owner of theContinue reading “Strict-Transport-Security for *.dev, *.app and more”

Google Internet Authority G3

For some time now, operating behind the scenes and going mostly unnoticed, Google has been changing the infrastructure used to provide HTTPS certificates for its sites and services. You’ll note that I said mostly. Over the last few months, I’ve periodically encountered complaints from users who try to load a Google site and get an unexpectedContinue reading “Google Internet Authority G3”

Chrome 59 on Mac and TeletexString Fields

Update: This change ended up getting backed out, after it was discovered that it impacted smartcard authentication. Thanks for self-hosting Chrome Dev builds, IT teams! A change quietly went into Chrome 59 that may impact your certificates if they contain non-ASCII characters in a TeletexString field. Specifically, these certificates will fail to validate on Mac, resulting inContinue reading “Chrome 59 on Mac and TeletexString Fields”