Copy/Paste Exfiltration
Input Fields with Copy Paste Protection
Copy and paste operations can be intercepted by malicious scripts. SmartField blocks copy, cut, paste, select, selectstart, contextmenu, dragstart, drag, and drop events at the capture phase.
The Attack
When copy/paste exfiltration targets a standard HTML input, the attacker can read the plaintext value directly from the DOM:
// Copy/Paste Exfiltration attack:
document.querySelector('input').value
// "SensitiveData123" ← stolen
The Protection
With SmartField, the same attack returns encrypted data:
// Same attack against SmartField:
document.querySelector('smart-field').value
// "eyJ2IjoxLCJpdiI6..." ← AES-256-GCM encrypted
The attacker gets 600+ characters of encrypted gibberish. Useless without the server's RSA-2048 private key.
13 Security Layers
SmartField does not rely on any single defense. It combines 13 independent security layers:
- Closed Shadow DOM (shadowRoot = null)
- AES-256-GCM authenticated encryption
- RSA-2048 key exchange
- WeakMap data isolation
- Event propagation blocking
- Anti copy/paste/select/drag
- Cipher character display
- Anti-screenshot scrambling
- Hidden metadata (type, name, length)
- Value injection blocking
- Non-configurable properties
- Anti-bot architecture
- HTTPS enforcement
Implementation
<!-- 2 lines. That's it. -->
<script src="https://cdn.smartfield.dev/v1/smartfield.js"></script>
<smart-field type="password" encrypt-key="/api/sf-key"></smart-field>
Frequently Asked Questions
How does SmartField protect against copy/paste exfiltration?+
Copy and paste operations can be intercepted by malicious scripts. SmartField blocks copy, cut, paste, select, selectstart, contextmenu, dragstart, drag, and drop events at the capture phase.
Does this require changes to my server?+
Minimal. Install our server SDK (Node.js, Python, Java, Go, PHP, or Ruby). Call sf.decrypt() on the encrypted payload. Your existing authentication and business logic stays the same.
Does it work with React, Vue, and Angular?+
Yes. SmartField is a standard Web Component. It works with any framework or no framework at all.
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