1Password Security Design.pdf

1Password provides robust security through client-generated end-to-end encryption, ensuring all cryptographic keys are created locally on users' devices. The service remains unaware of account passwords or keys, preventing server-side access to sensitive data. Stored data uses two-secret key derivation (2SKD) to eliminate cracking risks, while data in transit is triple-encrypted via TLS and proprietary transport encryption. Users exclusively control data sharing, requiring vault keys for access. Team-managed recovery keys allow authorized members to restore access if users forget passwords or lose keys, but 1Password cannot recover data independently due to end-to-end security.

The security design follows five core principles: privacy by design (systems avoid possessing sensitive data), trust the math (cryptography over human policies), people are part of the system (simplifying security without compromising expertise), openness (public scrutiny of security decisions), and know your tools (understanding cryptographic implementations). Account passwords and secret keys—both user-managed—are required to decrypt data, with each protected against distinct threats. This combination ensures data security through layered, user-controlled mechanisms.