Threat model
Assumptions worth
challenging.
The assets include owner authority, access secrets, content confidentiality and current-state integrity. The following adversaries and failures shape our acceptance gates.
Endpoint boundaryA compromised host.
The present process or operating system can read keys and plaintext. Ordinary browser code and hardware-backed key generation do not establish protected rendering.
Required evidence: a complete attested, non-exporting processing and display path on a named device and build.
Committee trustA colluding threshold.
Sufficient colluding share holders can decrypt retained old ciphertext. Threshold access is not protection from a malicious quorum with the required material.
Required evidence: a reviewed custody model, independent deployment, key lifecycle and explicit quorum-compromise assumptions.
State integrityA stale or dishonest observer.
An untrusted state source can lie. A valid signature or inclusion calculation alone does not establish a fresh, authoritative ownership state.
Required evidence: authenticated observations, challenge binding, freshness policy and refusal when required evidence is missing.
Replay & rollbackAn earlier state replayed.
Old requests, capabilities and device state can be retained. Local hash chaining does not prevent coordinated rollback of both records and their stored head.
Required evidence: nonrollbackable state inside the protected boundary, plus replay and restart tests.
Settlement & recoveryA chain change or crash.
Transactions may conflict, observations may reorganise, and a process can stop between steps. Bounded private-node recovery is not production durability.
Required evidence: canonical-state reconciliation, uncertain-access quarantine and reproducible fail-closed recovery.
Authority & key lossA lost key or abusive recovery.
Device replacement and owner-key recovery are different. In the current profile, losing the sole owner signing key is unrecoverable.
Required evidence: reviewed recovery that preserves one recognised possession without creating a hidden bypass authority.