Social Recovery
Never lose access, and make sure the right people can. Keeplas splits your master key into encrypted shards across trusted contacts — a quorum can restore your vault, but no single person ever can.
The cryptographic guarantees
- Shamir Secret Sharing. Your master key is split into 5 shards. A threshold you choose (2-of-5 by default) can rebuild it.
- Post-quantum wrapping. Each shard is wrapped with ML-KEM-768 (NIST FIPS 203), so it stays sealed even against future quantum attacks.
- Reconstructed on-device. Recovery happens on your contacts' devices. Keeplas never sees a raw shard or your reconstructed key.
- No collusion risk. Below the threshold, the shards reveal nothing. Not even Keeplas plus a single contact can open your vault.
How recovery works
- Invite trusted contacts. Add people you trust by email or phone. They confirm and receive an encrypted shard tied to their device.
- Choose your threshold. Pick how many contacts must cooperate — 2-of-5 by default. Lower is easier; higher resists collusion.
- Shards are distributed. Keeplas runs Shamir locally on your device, wraps each shard with ML-KEM-768, and sends one per contact. Plaintext shards never exist outside memory.
- When recovery is needed, contacts authorize the request from their devices. The threshold's worth of unwrapped shards reconstruct the master key — on a device, not on the server.
Picking a threshold
| Threshold | Recovery friction | Collusion resistance |
|---|---|---|
| 2-of-5 | Lowest | Lowest |
| 3-of-5 | Moderate | Stronger |
| 4-of-5 | High | Strongest |
2-of-5 is the default because it makes recovery actually feasible during a stressful moment. If you can pick five people who would not collude against you, this is a sound starting point. Move to 3-of-5 if any of your five contacts are connected through the same household, employer, or jurisdiction.
Picking contacts
Good contacts share three traits:
- Reachable — they will pick up the phone or check email within a few days.
- Trustworthy in your specific risk model — not just generally trustworthy, but trustworthy under the failure modes you actually worry about.
- Geographically or socially diverse — five contacts on the same hard drive defeats the purpose.
You can rotate contacts at any time. Removing a contact invalidates their shard immediately; their share of the key is regenerated and re-distributed.
What contacts can and cannot do
They can: participate in a recovery flow you (or Life Check) initiated; their device unwraps their shard and contributes to reconstruction.
They cannot: read your vault, see other contacts' shards, see the contents of any item, or initiate a recovery on their own. Below the threshold, their shard is mathematically useless.