Security
This page is the technical companion to Privacy: not what stays local, but how the sensitive parts are protected.
Vault encryption
The vault uses the platform’s Web Crypto API — real, standard cryptography, not obfuscation.
| Property | Value |
|---|---|
| Cipher | AES-256-GCM (authenticated encryption) |
| Key derivation | PBKDF2-SHA-256, 210,000 iterations |
| Salt | 16 random bytes, per item |
| IV | 12 random bytes, per item |
| Stored layout | base64( salt ‖ iv ‖ ciphertext+tag ) |
GCM is authenticated, so a tampered ciphertext fails to decrypt rather than returning garbage. The high PBKDF2 iteration count makes each master-password guess deliberately expensive; the per-item salt and IV mean two identical secrets never encrypt to the same bytes. Vaults created under an earlier 100,000-iteration build are re-keyed to 210,000 transparently the next time you unlock.
The master password
- Never stored. QlipLab keeps only a salted SHA-256 hash in
base64(salt):base64(hash)form. - Verified in constant time. The comparison uses a timing-safe check, so an attacker can’t learn the hash a byte at a time by measuring how long verification takes.
- Unrecoverable by design. There is no reset. If you lose the master password, the encrypted data stays encrypted — which is exactly the guarantee a vault has to make.
The key’s lifetime
The encryption key is derived from your master password in memory when you unlock the vault, held only while the vault is open, and cleared when it auto-locks (after 5 minutes of inactivity by default) or when you quit. It is never written to disk.
Brute-force resistance
Wrong master-password attempts trigger an escalating backoff — 3 failures → 3 seconds, and climbing — so the local database can’t be hammered with guesses at speed.
Platform protections
- macOS App Sandbox confines QlipLab to its own container. The one capability it requests for paste and shortcuts is the Accessibility permission you grant explicitly.
- Content Security Policy restricts where the app may connect — the report Worker and the editor CDN, nothing else.
- Signed updates. Updates are cryptographically signed and verified before they’re applied; a tampered update won’t install.
- Sanitized error reports. If you opt into crash reporting, stack traces have file paths stripped before they leave the machine, and no clipboard or vault content is ever included. See Privacy.
What is not encrypted, and why
Clipboard history and snippets are stored in plaintext in the local database. This is a deliberate trade-off: they hold everyday content, they need to be instantly searchable, and the database sits inside the OS sandbox with the app’s own file permissions. Anything that genuinely needs to be secret belongs in the vault, which is encrypted. Sensitive-looking clips are still detected and blurred in the UI so they don’t leak over your shoulder.
Reviewing it yourself
QlipLab is open source under Apache-2.0. The encryption, the detection patterns, and the report Worker are all in the public repository — the security claims on this page are things you can read the code for, not things you have to take on trust.