🛡️ Cyrillic URL Detector

Protect yourself from sophisticated phishing attempts using Cyrillic letters in URLs

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What is Cyrillic URL Detector?

This browser extension protects you against sophisticated phishing attacks that exploit Unicode characters. Attackers often create fake URLs by replacing Latin letters with visually identical Cyrillic characters. For example, the Latin 'a' (U+0061) looks identical to the Cyrillic 'а' (U+0430), but they're different characters that lead to different websites.

🔍 Real-Time Protection

Continuously monitors URLs as you browse, protecting you even in modern Single Page Applications (SPAs) where pages update dynamically.

⚠️ Visual Warnings

Displays a prominent red warning bar at the top of the page when Cyrillic characters are detected in the URL.

🎯 User-Friendly

Non-intrusive warnings that can be easily dismissed, while maintaining vigilant protection.

How it Works

When you visit a webpage containing Cyrillic characters in its URL, you'll immediately see this warning banner:

⚠️ Warning: This URL contains Cyrillic characters. It might be a phishing attempt.

For example, these URLs might look identical, but one uses Cyrillic characters:

Safe: example.com (Using standard Latin 'e')
Dangerous: еxample.com (Using Cyrillic 'е' - a completely different character)

While some Cyrillic URLs are legitimate (like Russian websites), be extra cautious when seeing Cyrillic characters in URLs of international websites or financial institutions.

Installation Guide

  1. Download the extension or source code
  2. Open Chrome and navigate to chrome://extensions/
  3. Enable "Developer mode" using the toggle in the top right
  4. Click "Load unpacked" and select the extension directory
  5. The extension will automatically start protecting you!
  6. The plugin actively monitors URLs for safety:
    Example of a legitimate Cyrillic URL (Russian Wikipedia): https://ru.wikipedia.org/wiki/Россия
    This is a legitimate Russian website using Cyrillic characters as expected. The extension will show a warning, but since this is a known Russian domain, it's safe to proceed.

Technical Details

The extension works by: