ShieldFive is built for people who are professionally responsible for other people's confidential files — accountants, financial advisors, and legal teams. This page explains, plainly, how the product supports that responsibility, and where its limits are.
Client-side encryption and its trust boundary
Files are encrypted on your device before upload. Your password never reaches our servers: the browser turns it into a separate login value with Argon2id and sends only that, and the key that opens your vault is derived separately and stays on your device. The app code is delivered by ShieldFive, so the client you are served is part of the trust boundary: client-side encryption does not establish that ShieldFive is technically unable to decrypt your files. See the security overview before deciding whether this model meets your requirements.
Web uploads default to the ML-KEM-1024/XChaCha20-Poly1305 hybrid format, with an AES-256-GCM fallback. Android also writes the hybrid format by default, with the same AES-256-GCM fallback, and reads both formats. The format used by a particular client matters; we do not promise post-quantum hybrid encryption for every upload.
Controls that support your obligations
ShieldFive is designed to help you meet your professional confidentiality, GDPR, and GLBA / FTC Safeguards obligations when you handle client data:
- End-to-end encryption in transit and at rest, with client-side, on-device key generation.
- Secure share links with expiry dates, download limits, and passphrase protection (Argon2id).
- EU data residency: encrypted data is stored in the EU, under EU jurisdiction.
- The Article 28 Data Processing Agreement is published at /privacy/dpa and included on every seat — not gated behind an enterprise tier. Its terms apply unchanged; email [email protected] to have a copy executed for your organisation.
ShieldFive supports these obligations; it does not discharge them. Compliance remains the professional's responsibility, and this page is neither a certification nor a legal opinion.
Transparency instead of a certificate
We have not yet purchased a third-party audit, so instead we let you verify us directly:
- Open-source cryptography. Our crypto library, @shieldfive/crypto, is public under Apache-2.0, so you can read the exact code that encrypts your files.
- A published internal security review: 31 findings (0 critical, 0 high, 7 medium, 17 low, 7 informational), 26 of them fixed.
What we do not claim
Plain limits, so you can trust what we do claim:
- No completed third-party or external security audit yet.
- No SOC 2 or ISO 27001 certification.
- The cryptography library is open source; the web and mobile applications themselves are closed source.
- No US HIPAA Business Associate Agreement — HIPAA governs health data, which is outside an accounting or legal document workflow.
If your firm requires a completed external audit or a signed BAA today, ShieldFive is not the right fit yet — and we would rather tell you that here than in a sales call.