The by-id user-management handlers use findById, which has no role
filter, so supplying the synthetic GUEST_USER_ID let an admin delete,
re-role, reset-password, and read/write permissions on the shared guest
principal (privilege-escalation / DoS / credential-login holes).
- web/api/users.ts: 404-guard every :id handler against GUEST_USER_ID
(DELETE, reset-password, role, GET/PUT permissions).
- data/users.ts: defense-in-depth — setRoleIfNotLastAdmin and
deleteUserIfNotLastAdmin return "not_found" for any role=guest row.
- web/api/session.ts: wrap POST /guest createSession in try/catch so a
missing guest row yields 503 instead of an unhandled 500.
- Tests: data-layer guest-protection + users-router 404 by-id guards.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Adds an admin/member role to WebUI auth. /api/users and /api/audit
are now gated by a requireAdmin middleware; all other authenticated
endpoints accept both roles. Schema migration defaults all existing
users to admin to preserve access. POST /api/users defaults new users
to member; first-run setup always creates an admin. Adds PATCH
/api/users/:id/role with last-admin demotion and deletion guards.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
