Escrow Security for iCloud Keychain
7 hours ago
- #iCloud Security
- #Hardware Security Modules
- #Keychain Escrow
- iCloud Keychain uses a secure escrow infrastructure backed by Hardware Security Modules (HSMs) to encrypt and protect escrow records.
- Keychain recovery requires multi-factor authentication: iCloud account and password, SMS verification to a registered phone, and the iCloud security code verified via Secure Remote Password (SRP) without sending the code to Apple.
- HSMs independently verify attempt limits, with a majority vote needed to unwrap and send the escrow record to the user's device for decrypting the keychain.
- Only 10 authentication attempts are allowed; after several failures, the record locks, and after the 10th failure, the HSM destroys the record permanently to prevent brute-force attacks.
- HSM firmware enforces these policies, with administrative access cards destroyed to prevent alterations; any tampering triggers private key deletion and notifies users to reenroll their escrow records.