Regular readers of my blogs know that I love browser extensions. Extensions can make using your browser more convenient, fun, and secure. Unfortunately, extensions can also break web apps in bizarre or amusing ways, dramatically slow your browser performance, leak your personal data, or compromise your device. The designers of the Chromium extension system createdContinue reading “Browser Extensions: Powerful and Potentially Dangerous”
Category Archives: tech
Cloaking, Detonation, and Client-side Phishing Detection
Today, most browsers integrate security services that attempt to protect users from phishing attacks: for Microsoft’s Edge, the service is Defender SmartScreen, and for Chrome, Firefox, and many derivatives, it’s Google’s Safe Browsing. URL Reputation services do what you’d guess — they return a reputation based on the URL, and the browser will warn/block loadingContinue reading “Cloaking, Detonation, and Client-side Phishing Detection”
How Downloads Work
I delivered a one hour session on the internals of file downloads in web browsers at THAT Conference 2024. The slides are here and a MP3 of the talk is available. If you’d prefer to read, much of the content in the talk is found in this blog’s posts that have a Download tag.
The Blind Doorkeeper Problem, or, Why Enclaves are Tricky
When trying to protect a secret on a client device, there are many strategies, but most of them are doomed. However, as a long-standing problem, many security experts have tried to chip away at its edges over the years. Over the last decade there’s been growing interest in using enclaves as a means to protectContinue reading “The Blind Doorkeeper Problem, or, Why Enclaves are Tricky”
Defense Techniques: Blocking Protocol Handlers
Application Protocols represent a compelling attack vector because they’re the most reliable and cross-browser compatible way to escape a browser’s sandbox, and they work in many contexts (Office apps, some PDFs handlers, some chat/messaging clients, etc). Some protocol handlers are broadly used, while others are only used for particular workflows which may not be relevantContinue reading “Defense Techniques: Blocking Protocol Handlers”