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Browsers
What is Browser Extension Security?
The risks and considerations of browser extensions, which can access your browsing data and potentially exfiltrate sensitive information.
Browser extensions are one of the most overlooked privacy risks — they can see everything you do in your browser.
What Extensions Can Access
- All website content you visit
- Cookies and authentication tokens
- Form data including passwords
- Browsing history
- Network requests
Risks
- Extensions can be sold to new owners who add malicious code
- Legitimate extensions can be compromised via supply chain attacks
- Many free extensions monetize by collecting and selling browsing data
- Chrome extensions don't require a security review
Safe Extension Practices
- Install only essential extensions
- Prefer open-source extensions (uBlock Origin, Privacy Badger)
- Review permissions before installing
- Audit installed extensions periodically
- Use Firefox (stricter extension sandboxing than Chrome)
Related Terms
Browser Fingerprinting
A tracking technique that collects information about your browser, device, and settings to create a unique identifier. Unlike cookies, fingerprints are nearly impossible to delete and can track you across websites without your knowledge or consent.
Third-Party Tracking
The practice of monitoring user behavior across multiple websites using embedded scripts, pixels, cookies, and fingerprinting techniques.
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