Capturing Logs for Debugging SmartScreen

The Microsoft Edge browser makes use of a service called Microsoft Defender SmartScreen to help protect users from phishing websites and malicious downloads. The SmartScreen service integrates with a Microsoft threat intelligence service running in the cloud to quickly block discovered threats. As I explained last year, the SmartScreen service also helps reduce spurious securityContinue reading “Capturing Logs for Debugging SmartScreen”

Edge’s Super-Res Image Enhancement

One interesting feature that the Edge team is experimenting with this summer is called “SuperRes” or “Enhance Images.” This feature allows Microsoft Edge to use a Microsoft-built AI/ML service to enhance the quality of images shown within the browser. You can learn more about how the images are enhanced (and see some examples) in theContinue reading “Edge’s Super-Res Image Enhancement”

Extending Fiddler’s ImageView

Fiddler’s ImageView Inspector offers a lot of powerful functionality for inspecting images and discovering ways to shrink an image’s byte-weight without impacting its quality. Less well-known is the fact that the ImageView Inspector is very extensible, such that you can add new tools to it very simply. To do so, simply download any required executablesContinue reading “Extending Fiddler’s ImageView”

Analyzing Network Traffic Logs (NetLog json)

Previously, I’ve described how to capture a network traffic log from Microsoft Edge, Google Chrome, and applications based on Chromium or Electron. In this post, I aim to catalog some guidance for looking at these logs to help find the root cause of captured problems and otherwise make sense of the data collected. Last Update:Continue reading “Analyzing Network Traffic Logs (NetLog json)”

Capture Network Logs (NetLog) from Edge and Chrome (and Electron and WebView2)

Problems in accessing websites can often be found and fixed if the network traffic between the browser and the website is captured as the problem occurs and the resulting log file is shared with engineers. This short post explains how to capture such log files. Capturing Network Traffic Logs If someone asked you to readContinue reading “Capture Network Logs (NetLog) from Edge and Chrome (and Electron and WebView2)”

Firefox and Fiddler – Easier than Ever

In a world where software and systems seem to march inexorably toward complexity, I love it when things get simpler. Years ago, Firefox required non-obvious configuration changes to even send traffic to Fiddler. Eventually, Mozilla changed their default behavior on Windows to adopt the system’s proxy, meaning that Firefox would automatically use Fiddler when it was attached,Continue reading “Firefox and Fiddler – Easier than Ever”

Chrome Deprecates Subject CN Matching

If you’re using a Self-Signed certificate for your HTTPS server, a deprecation coming to Chrome may affect your workflow. Chrome 58 will require [why?] that certificates specify the hostname(s) to which they apply in the SubjectAltName field; values in the Subject field will be ignored. This follows a similar change in Firefox 48. If impacted,Continue reading “Chrome Deprecates Subject CN Matching”

Using Fiddler With iOS 10 and Android 7

If you’ve tried to use Fiddler with iOS10 beta or Android 7 Nougat, you have probably found that HTTPS decryption isn’t working, even if you use the latest Fiddler and the Fiddler Certificate Maker add-on. Unfortunately, at the moment both platforms are broken, but for different reasons. In both cases, the client will fail toContinue reading “Using Fiddler With iOS 10 and Android 7”

Silliness – Fiddler Blocks Malware

Enough malware researchers now depend upon Fiddler that some bad guys won’t even try to infect your system if you have Fiddler installed. The Malware Bytes blog post has the details, but the gist of it is that the attackers use JavaScript to probe the would-be victim’s PC for a variety of software. Beyond Kaspersky,Continue reading “Silliness – Fiddler Blocks Malware”