How I Would Fix exposed API keys and missing auth in a Circle and ConvertKit client portal Using Launch Ready.

How I Would Fix exposed API keys and missing auth in a Circle and ConvertKit client portal Using Launch Ready

The symptom is usually obvious: someone can open the client portal, view network requests, or inspect page source and find Circle or ConvertKit API keys, then hit protected data without logging in. In business terms, that means customer data exposure, account abuse, support load, and a launch blocker if this is live.

The most likely root cause is simple: the app was built fast with client-side calls to third-party APIs, but auth was never enforced at the edge or backend. The first thing I would inspect is whether any secrets are shipped to the browser, then I would check whether the portal trusts front-end state instead of server-verified sessions.

Triage in the First Hour

1. Open the live portal in an incognito window. 2. Inspect page source and browser network requests for:

• API keys
• bearer tokens
• Circle member IDs
• ConvertKit subscriber data

3. Check Cloudflare logs or hosting logs for unusual request spikes. 4. Review the auth flow:

• Is there login at all?
• Is there route protection?
• Are pages only hidden in the UI, not actually protected?

5. Search the repo for secret names:

• `CIRCLE_API_KEY`
• `CONVERTKIT_API_KEY`
• `CONVERTKIT_SECRET`
• `NEXT_PUBLIC_` or any client-exposed env vars

6. Inspect deployment environment variables in Vercel, Netlify, Render, Railway, or your host. 7. Review recent builds and commits for rushed changes around:

• onboarding
• embedded widgets
• direct fetch calls from React components

8. Verify whether Circle and ConvertKit are being called from:

• browser code
• server actions
• backend routes

9. Check account permissions in Circle and ConvertKit. 10. Confirm whether any exposed key has already been rotated.

A quick command I would run during triage:

grep -R "CIRCLE\|CONVERTKIT\|NEXT_PUBLIC" . --exclude-dir=node_modules --exclude-dir=.next

If I find keys in client code or public env vars, I treat it as a production incident until proven otherwise.

Root Causes

| Likely cause | What it looks like | How I confirm it | |---|---|---| | Secrets embedded in frontend code | API key appears in JS bundle or network calls | Search built assets and browser requests | | Missing route protection | Any visitor can open portal pages directly | Test URLs in incognito with no session | | Weak auth based on UI only | Buttons hide content but backend still serves it | Call protected endpoints without login | | Over-permissive API keys | One leaked key can read or modify too much | Review scopes and connected account permissions | | Bad environment variable setup | Public env vars used for private secrets | Check host config and build settings | | No server-side session validation | Frontend assumes user is logged in | Inspect middleware, guards, and backend checks |

The biggest mistake here is assuming that hiding a page means securing it. If the data can be fetched without server-side authorization, the portal is not secure.

The Fix Plan

I would fix this in a strict order so we stop exposure first and avoid breaking production.

1. Rotate exposed keys immediately.

• Revoke old Circle and ConvertKit credentials.
• Issue new least-privilege keys.
• Confirm old tokens no longer work.

2. Remove all secrets from client code.

• Move API access behind server routes, server actions, or a backend service.
• Ensure private env vars never use public prefixes like `NEXT_PUBLIC_`.

3. Add real authentication.

• Use one trusted identity layer for the portal.
• Require login before any customer data loads.
• Enforce session checks on every protected route and API endpoint.

4. Add authorization checks per user.

• A logged-in user should only see their own records.
• Never trust IDs from the browser without verifying ownership server-side.

5. Lock down Circle and ConvertKit access patterns.

• Use read-only scopes where possible.
• Split admin actions from customer-facing reads.
• Keep webhook secrets separate from API keys.

6. Put sensitive calls behind a secure backend boundary.

• Browser -> authenticated app route -> third-party API
• Never browser -> third-party API directly for private data

7. Add logging without leaking secrets.

• Log auth failures, denied access, and unusual request patterns.
• Redact tokens, emails where needed, and personal data from logs.

8. Harden delivery infrastructure as part of Launch Ready.

• Cloudflare DNS setup
• SSL enforcement
• Redirects and subdomains
• DDoS protection
• Caching where safe
• Uptime monitoring

9. Clean up deployment hygiene.

• Separate dev, staging, and prod environments.
• Store secrets only in deployment environment variables or secret managers.
• Verify build output does not contain private values.

My preference is to fix auth first, then refactor secret handling second. If you do it the other way around, you can spend hours cleaning code while the portal stays exposed.

Regression Tests Before Redeploy

I would not ship this without testing both security behavior and basic product flow.

1. Anonymous access test:

• Open all portal URLs in incognito.
• Expected result: redirect to login or 401/403 response.

2. Session enforcement test:

• Log out manually.
• Refresh protected pages.
• Expected result: no private data loads.

3. Authorization test:

• Use one customer account to attempt access to another customer's records.
• Expected result: denied every time.

4. Secret exposure test:

grep -R "api_key\|secret\|token" .next dist build 2>/dev/null

Expected result: no private secrets in built assets.

5. Network inspection test:

• Open DevTools on key pages.
• Expected result: no direct third-party API calls containing private credentials from the browser.

6. Webhook validation test: - Send invalid webhook payloads to Circle or ConvertKit endpoints if applicable. Expected result: rejected unless signature verification passes.

7. Negative login test:

• Try expired sessions, bad passwords, tampered cookies, and replayed links.
• Expected result: access denied cleanly.

8. Smoke test for business flows:

• Login
• View portal dashboard
• Load subscriber or membership data
• Update allowed profile fields if supported
• Logout

Acceptance criteria I would use before release:

• 0 exposed private API keys in client bundles or public env vars.
• 100 percent of protected routes require server-side auth checks.
• 100 percent of customer records are scoped by authenticated user ID or tenant ID.
• No critical errors during smoke testing across Chrome mobile and desktop.
• Uptime monitoring returns green after deploy for at least 30 minutes.

Prevention

I would put guardrails around code review, deployment, and monitoring so this does not happen again.

• Security review checklist before merge:

- Are any secrets used in frontend code? - Is every protected endpoint checking identity? - Are scopes minimal? - Are logs redacted?

• CI gates:

- Secret scanning on every push - Linting plus type checks - Basic auth tests on protected routes

• Monitoring:

- Alert on unusual traffic spikes to portal routes - Alert on repeated auth failures - Monitor uptime from multiple regions

• UX guardrails:

- Show clear login states instead of broken blank screens - Add helpful error messages for expired sessions - Avoid exposing partial sensitive data while loading

• Performance guardrails:

- Keep portal pages under a 2 second LCP target on desktop where possible - Avoid heavy third-party scripts that slow login flows - Cache safe public assets through Cloudflare

• AI red teaming mindset if AI features exist later:

- Test prompt injection against any assistant connected to customer records - Block tool misuse that could leak subscriber lists or member details

For a client portal like this, security issues often become conversion issues too. If customers cannot trust login behavior or see strange errors after a leak scare, they will stop using the product even if the UI looks fine.

When to Use Launch Ready

Use Launch Ready when you need me to stabilize the product fast instead of turning this into a long rebuild.

This sprint fits best when:

• your portal is already built but unsafe to launch,
• you have exposed secrets or broken auth,
• you need production deployment cleaned up quickly,
• you want Cloudflare protection plus monitoring before sending traffic,
• you need a handover checklist so your team can keep it running.

What I would ask you to prepare:

1. Repo access with current branch state. 2. Hosting access for prod and staging. 3. Cloudflare account access if DNS sits there. 4. Circle admin details plus relevant workspace settings. 5. ConvertKit admin access plus forms/tags/webhooks info if used by the portal. 6. A short list of protected user journeys: - login dashboard view member content view subscription update flow if applicable

If you want this handled properly without dragging it into a two-week fire drill, book here: https://cal.com/cyprian-aarons/discovery

Delivery Map

References

1. roadmap.sh Cyber Security Best Practices: https://roadmap.sh/cyber-security 2. roadmap.sh API Security Best Practices: https://roadmap.sh/api-security-best-practices 3. roadmap.sh Code Review Best Practices: https://roadmap.sh/code-review-best-practices 4. Cloudflare Security Docs: https://developers.cloudflare.com/security/ 5. ConvertKit Help Center: https://help.convertkit.com/

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Take the next step

If this is a problem in your product right now, here is what to do next:

• [Use the free Cyprian tools](/tools) - estimate cost, score app risk, check launch readiness, or pick the right service sprint.

• [Book a discovery call](/contact) - I will tell you honestly whether you need a sprint or if you can DIY the next step.

*Written by Cyprian Tinashe Aarons - senior full-stack and AI engineer helping founders rescue, launch, automate, and scale AI-built products.*