Passkeys – Syncable WebAuthN credentials

Passwords have lousy security properties, and if you try to use them securely (long, complicated, and different for every site), they often have horrible usability as well. Over the decades, the industry has slowly tried to shore up passwords’ security with multi-factor authentication (e.g. one-time codes via SMS, ToTP authenticators, etc) and usability improvements (e.g.Continue reading “Passkeys – Syncable WebAuthN credentials”

Certificate Revocation in Microsoft Edge

When you visit a HTTPS site, the server must present a certificate, signed by a trusted third-party (a Certificate Authority, aka CA), vouching for the identity of the bearer. The certificate contains an expiration date, and is considered valid until that date arrives. But what if the CA later realizes that it issued the certificateContinue reading “Certificate Revocation in Microsoft Edge”

Unexpectedly HTTPS?

While I’m a firm believer that every site should be using HTTPS, sadly, not every site is yet doing so. Looking at Chrome data, today around 92% of navigations are HTTPS: …and the pages loaded account for around 95% of browsing time: Browsers are working hard to get these numbers up, by locking down non-secureContinue reading “Unexpectedly HTTPS?”

Smarter Defaults by Paying Attention

As a part of every page load, browsers have to make dozens, hundreds, or even thousands of decisions of varying levels of importance: should a particular API be available? Should a resource load be permitted? Should script be allowed to run? Should video be allowed to start playing automatically? Should cookies or credentials be sentContinue reading “Smarter Defaults by Paying Attention”

MoarTLS: Non-Secure Download Blocking

With little fanfare, an important security change has arrived on the web. Now, all major browsers (except Safari) block non-secure downloads from a secure page. Browser Version Behavior Edge 94+ Block with right-click “Keep” button Chrome 94 Block Silently Firefox 93 Block with “Allow download” button Brave 1.30.89 Block Silently Opera 79.0.4143.72 Block Silently SafariContinue reading “MoarTLS: Non-Secure Download Blocking”

Offline NetLog Viewing

A while back, I explained how you can use Telerik Fiddler or the Catapult NetLog Viewer to analyze a network log captured from Microsoft Edge, Google Chrome, or another Chromium or Electron-based application. While Fiddler is a native app that runs locally, the Catapult NetLog Viewer is a JavaScript application that runs in your browser.Continue reading “Offline NetLog Viewing”

Web Proxy Authentication

Last year, I wrote about how the new Microsoft Edge’s adoption of the Chromium stack changed proxy determination away from the Windows Service (WinHTTP Proxy Service) to similar but not identical code in Chromium. This change mostly goes unnoticed, but it can have performance and functionality implications. In today’s post, I want to explore anotherContinue reading “Web Proxy Authentication”

Sandboxing vs. Elevated Browsing (As Administrator)

The Web Browser is the most security-critical application on most users’ systems– it accepts untrusted input from servers anywhere in the world, parses that input using dozens to hundreds of parsers, and renders the result locally as fast as it can. For performance reasons, almost all code in almost all browsers is written in memory-unsafeContinue reading “Sandboxing vs. Elevated Browsing (As Administrator)”

Local Data Encryption in Chromium

Back in February, I wrote about browser password managers and mentioned that it’s important to understand the threat model when deciding how to implement features and their security protections. Generally speaking, “keeping secrets from yourself” is a fool’s errand, so it’s a waste of time and effort to encrypt data if you have to storeContinue reading “Local Data Encryption in Chromium”