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Cyber Security

Cookie Theft: Why Websites Can’t Always Stop It

TL;DR

Browser cookies are small files websites use to remember you. They can be stolen, allowing someone else to pretend to be you on those sites. While websites try to protect them, it’s very difficult to prevent all cookie theft because of how the internet and browsers work. You need to take steps to protect yourself – strong passwords, being careful what software you install, and keeping your browser updated are key.

Why Cookies Get Stolen

Cookies themselves aren’t inherently dangerous; they’re useful for things like staying logged in or remembering shopping cart items. However, if a cookie is stolen, someone can use it to access your account without needing your password. Here’s how that happens:

  • Malware: Viruses and other malicious software on your computer can steal cookies directly from your browser’s files.
  • Network Sniffing: If you’re using an unsecured Wi-Fi network (like a public hotspot), someone could intercept the data being sent between your computer and the website, including your cookies.
  • Cross-Site Scripting (XSS): A flaw in a website’s code can allow attackers to inject malicious scripts that steal cookies from visitors. This is a website problem, not something you directly cause.
  • Browser Extensions: Rogue or compromised browser extensions can access and steal your cookies.

Why Websites Aren’t Always Able To Prevent It

Websites face several challenges when trying to prevent cookie theft:

  • Cookies are sent automatically: Your browser sends cookies with every request to the website, so there’s no easy way for a website to know if it’s a legitimate request or someone using a stolen cookie.
  • HTTP Protocol Limitations: The basic HTTP protocol (used by most websites) isn’t designed with strong security in mind. While HTTPS helps encrypt data in transit, it doesn’t prevent cookies from being used once they reach the server.
  • Third-Party Cookies: Websites often use cookies set by other companies (third-party cookies) for advertising and tracking. These are even harder to control because the website doesn’t directly manage them.
  • Browser Compatibility: Different browsers handle cookies differently, making it difficult to implement a consistent security solution across all platforms.

How To Protect Yourself – Step-by-Step

  1. Keep Your Software Updated: This is the most important step! Updates often include security patches that fix vulnerabilities.
    • Operating System: Windows, macOS, Linux – enable automatic updates.
    • Browser: Chrome, Firefox, Safari, Edge – check for updates regularly (usually in the browser’s settings).
    • Antivirus/Anti-Malware Software: Keep your antivirus software up to date and run regular scans.
  2. Use Strong, Unique Passwords: Don’t reuse passwords across different websites. A password manager can help you create and store strong passwords.
  3. Enable Two-Factor Authentication (2FA): Whenever possible, enable 2FA on your important accounts. This adds an extra layer of security beyond just a password.
  4. Be Careful What You Install: Only install software from trusted sources. Read reviews and check permissions before installing anything.
  5. Review Your Browser Extensions: Regularly review the extensions you have installed and remove any that you don’t recognize or no longer need.
    • Chrome: Type chrome://extensions in the address bar.
    • Firefox: Type about:addons in the address bar.
  6. Use HTTPS Everywhere: Most websites now use HTTPS, which encrypts data between your computer and the website. Make sure the website address starts with “https://”. Your browser usually indicates this with a padlock icon.
  7. Clear Cookies Regularly: Clearing cookies removes any stored information, including stolen ones. Be aware that this will log you out of websites.
    • Chrome: Settings > Privacy and security > Clear browsing data. Select “Cookies and other site data” and choose a time range (e.g., All time).
    • Firefox: Settings > Privacy & Security > Cookies and Site Data > Clear Data.
  8. Consider Using a Password Manager with Built-in Cookie Protection: Some password managers offer features to help protect your cookies from theft.
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