Keypeur

Security

Last updated: 2026-07-15

The model

Keypeur is built on one decision: your data never leaves your device. The whole vault (passwords, usernames, site addresses, notes, two-factor secrets and passkeys, metadata included) lives in a single encrypted block inside your browser's extension storage. The key that opens it is derived from your master password and exists only in memory while the vault is unlocked; closing the browser locks the vault.

No network, by construction

The extension makes no network requests of any kind. There is no account, no sync server, no telemetry and no third-party service. What never travels cannot be intercepted, and a server that does not exist cannot be breached. You can verify this claim yourself with your browser's developer tools.

Any version that changed this behaviour would first have to be released and reviewed through the Chrome Web Store: data collection cannot appear silently.

What we assume

The design assumes the page you visit is hostile. Nothing is ever filled without a gesture from you. Site matching is strict, so a login saved for one site is never offered to another. Sign-up forms are never filled automatically. The small interfaces Keypeur places on pages are isolated so the page cannot read what they display.

With quick unlock, your fingerprint or face is checked by your operating system: the extension never sees or stores any biometric data.

What we do not defend against

A compromised computer or browser (malware, a keylogger, an extension with debugging privileges) can defeat any password manager, including this one. A forgotten master password is unrecoverable by design: there is no backdoor, no escrow, no reset. And the vault exists only in your browser profile: without an exported backup, deleting the profile deletes the vault. Export backups regularly; the extension reminds you to.

Reporting a vulnerability

If you believe you have found a security issue in Keypeur, report it privately to contact@keypeur.com. Please do not publish it before a fix has shipped.