Common Threats to Plan For
- Insecure direct object references (IDOR) across tenants.
- Missing authorization checks on API routes.
- Session fixation, weak cookie settings, or token leakage.
- Privilege escalation due to inconsistent RBAC rules.
Rule: authenticate the user and authorize every action.
Practical Patterns (2026)
1) Prefer server-validated sessions
- Keep session state on the server or in signed cookies.
- Limit session lifetime and rotate tokens when needed.
2) Centralize authorization
- Define permissions and policies once, reuse everywhere.
- Do not scatter “if role === admin” checks across the codebase.
3) Audit logs for sensitive actions
- Log role changes, billing actions, exports, and impersonation.
- Store actor + target + timestamp + metadata.
Examples
Example RBAC Rules
| Action | Allowed roles | Audit? |
|---|---|---|
| Invite teammate | Owner, Admin | Yes |
| Export data | Owner, Admin | Yes |
| View billing | Owner, Billing | No |
| Change plan | Owner | Yes |
Example IDOR Fix
- Bad: GET /api/invoices?id=123 returns invoice without tenant check
- Good: validate user session → check invoice belongs to user’s org → return
Security Checklist
Sessions
- Secure cookies (HttpOnly, Secure, SameSite)
- Short lifetimes for sensitive apps
- Logout invalidates sessions properly
Authorization
- Policy checks on every mutation
- Tenant isolation enforced everywhere
- Admin tools protected
Audit logs
- Role changes recorded
- Billing events recorded
- Exports recorded
Operational
- Error monitoring enabled
- Rate limiting where needed
- Backups for critical data
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