Security Audit: Spacecraft Telemetry Security

Attack Surface & Mitigations

1. Machine Authentication: Machine endpoints require X-Ingest-Key validated using constant-time crypto.timingSafeEqual comparison against SHA-256 hashes to prevent timing attacks.
2. Replay Attack Defense: Idempotency keys with unique payload digests block replayed telemetry packets.
3. Audit Ledger Integrity: Audit events are cryptographically hashed and linked, creating an immutable ledger that reveals any local or ground record tampering.
4. Data Redaction: Telemetry transmitted to Earth is role-redacted to protect astronaut medical privacy under NASA flight surgeon regulations.