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”

Compression Context

ZIP is a great format—it’s extremely broadly deployed, relatively simple, and supports a wide variety of use-cases pretty well. ZIP is the underlying format beneath Java (.jar) Archives, Office (docx/xlsx/pptx) files, Fiddler (.saz) Session Archive ZIP files, and many more. Even though some features (Unicode filenames, AES encryption, advanced compression engines) aren’t supported by allContinue reading “Compression Context”

Downloads and the Mark-of-the-Web

Last update: June 17, 2026 tl;dr: Download apps can taint a file originating from the web so that other apps will handle it more carefully. Background To help protect the user and their device, Windows and its applications will often treat files originating from the Internet more cautiously than files generated locally. The Windows SecurityContinue reading “Downloads and the Mark-of-the-Web”

Building the moarTLS Analyzer

I’m passionate about building tools that help developers and testers discover, analyze, and fix problems with their sites. Some of the first code I ever released was a set of trivial JavaScript-based browser extensions for IE5. I later used the more powerful COM-based extensibility model to hack together some add-ons that would log ActiveX controlsContinue reading “Building the moarTLS Analyzer”

Seek and Destroy Non-Secure References Using the moarTLS Analyzer

tl;dr: I made a Chrome Extension that finds security vulnerabilities.It’s now available for Firefox too! To secure web connections, TLS-enabling servers is only half the battle; the other half is ensuring that TLS is used everywhere. Unfortunately, many HTTPS sites today include insecure references that provide an network-based attacker the opportunity to break into theContinue reading “Seek and Destroy Non-Secure References Using the moarTLS Analyzer”