Replaces the insecure token-in-localStorage approach with a header-based impersonation system backed by cache sessions and MFA verification. Key changes: - New impersonation_sessions audit table (immutable, ULID PK) - MFA verification required to start impersonation (TOTP/email/backup) - X-Impersonate-User header + HandleImpersonation middleware - Per-request auth context swap (admin session never modified) - IP pinning, sensitive route blocking, no nesting, sliding 60-min TTL - Activity log auto-tagged with impersonated_by during sessions - Frontend: sessionStorage, BroadcastChannel sync, countdown timer - ImpersonateDialog with reason + MFA verification flow - 26 comprehensive tests covering core, middleware, audit, lifecycle Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
592 B
592 B