Category Archives: tech

Attack Techniques: PayPal Invoice Scams

Today in “Attack techniques so stupid, they can’t possibly succeed… except they do!” — we look at Invoice Scams. PayPal and other sites allow anyone (an attacker) to send anyone (their victims) an invoice containing the text of the attacker’s choosing. In this attack technique, PayPal sends you an email suggesting that the attacker alreadyContinue reading “Attack Techniques: PayPal Invoice Scams”

Attack Techniques: Trojaned Clipboard

Today in “Attack techniques so stupid, they can’t possibly succeed… except they do!” — the trojan clipboard technique. In this technique, the attacking website convinces the victim to paste something the site has silently copied to the user’s clipboard into a powerful and trusted context. A walkthrough of this attack can be found in theContinue reading “Attack Techniques: Trojaned Clipboard”

Attack Techniques: Remote Control Software

In yesterday’s post, I outlined the two most successful (and stupid simple) attack techniques that you might not expect to work (and you’d be so very wrong): Today, let’s explore number 3: “Please give me control of your computer so I can, uh, fix it?“ In this attack, an attacker convinces you that there’s someContinue reading “Attack Techniques: Remote Control Software”

ERR_BLOCKED_BY_CLIENT and HTML5 Sandbox

Recently, many Microsoft employees taking training courses have reported problems accessing documents linked to in those courses in Chrome and Edge. In Edge, the screen looks like this: But the problem isn’t limited to Microsoft’s internal training platform, and can be easily reproduced in Chrome: What’s going on? There are a number of root causesContinue reading “ERR_BLOCKED_BY_CLIENT and HTML5 Sandbox”

Attacker Techniques: Gesture Jacking

A few years back, I wrote a short explainer about User Gestures, a web platform concept whereby certain sensitive operations (e.g. opening a popup window) will first attempt to confirm whether the user intentionally requested the action. As noted in that post, gestures are a weak primitive — while checking whether the user clicked orContinue reading “Attacker Techniques: Gesture Jacking”

pushState and URL Blocking

The Web Platform offers a handy API called pushState that allows a website’s JavaScript to change the URL displayed in the address bar to another URL within the same origin without sending a network request and loading a new page. The pushState API is handy because it means that a Web Application can change theContinue reading “pushState and URL Blocking”

Browser Extensions: Powerful and Potentially Dangerous

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”

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 expect — they return a reputation based on the URL, and the browser will warn/block loadingContinue reading “Cloaking, Detonation, and Client-side Phishing Detection”