Fly.io
Security FAQ

What security issues do Fly.io apps have?

Get instant answers about your app's security.

Short Answer

Fly.io apps surface a predictable distribution of issues: 0 critical-impact classes (none), 1 high-impact, 3 medium-or-below. The critical ones are what cause data breaches.

Detailed Answer

High-severity issues

  • **Secrets synchronization across regions**: A common failure mode in Fly.io applications: secrets synchronization across regions. Left unchecked, this can lead to data exposure, unauthorized access, or service abuse.

Medium/low-severity issues

  • **Edge deployment security**: A common failure mode in Fly.io applications: edge deployment security. Left unchecked, this can lead to data exposure, unauthorized access, or service abuse.
  • **Private networking configuration**: A common failure mode in Fly.io applications: private networking configuration. Left unchecked, this can lead to data exposure, unauthorized access, or service abuse.
  • **Volume and persistence security**: A common failure mode in Fly.io applications: volume and persistence security. Left unchecked, this can lead to data exposure, unauthorized access, or service abuse.

Why these are the issues specific to Fly.io

Fly.io apps ship with a recognizable stack (postgres, supabase). The issue list above is what appears when you scan that specific combination. A Firebase-backed app would have a different top-5; a self-hosted Postgres deployment would have yet another. Context is everything.

What VAS checks in a Fly.io scan

  • **Secrets Config** — Check secrets management setup.
  • **Network Security** — Review private networking.
  • **App Security** — Analyze application security.
  • **Headers** — Verify security headers.

Security Research & Statistics

10.3%

of Lovable applications (170 out of 1,645) had exposed user data in the CVE-2025-48757 incident

Source: CVE-2025-48757 security advisory

4.45 million USD

average cost of a data breach in 2023

Source: IBM Cost of a Data Breach Report 2023

500,000+

developers using vibe coding platforms like Lovable, Bolt, and Replit

Source: Combined platform statistics 2024-2025

Expert Perspectives

There's a new kind of coding I call 'vibe coding', where you fully give in to the vibes, embrace exponentials, and forget that the code even exists.

Andrej KarpathyFormer Tesla AI Director, OpenAI Co-founder

Vibe coding your way to a production codebase is clearly risky. Most of the work we do as software engineers involves evolving existing systems, where the quality and understandability of the underlying code is crucial.

Simon WillisonSecurity Researcher, Django Co-creator

Check Your Fly.io App's Security

VAS scans for all the security issues mentioned above. Get a comprehensive security report in minutes.

Get Starter Scan

More Questions About This Topic

Which Fly.io security issue is most dangerous?

Secrets synchronization across regions. A common failure mode in Fly.io applications: secrets synchronization across regions. Left unchecked, this can lead to data exposure, unauthorized access, or service abuse. This is the highest-impact finding because it tends to expose the full dataset or grant lateral movement in one step. The fix: Move all secrets server-side (environment variables, serverless functions). Rotate any keys previously in frontend code. Audit bundles for leftover credentials before each deploy.

Are these issues unique to Fly.io, or do they appear across platforms?

The patterns overlap with railway, render, vercel — all vibe-coding platforms share the "AI-generated code prioritizes functionality over security" problem. But the *specific manifestation* differs per platform. An exposed Supabase anon key is structurally different from an exposed Firebase config, which is different from an exposed Postgres connection string. The right scan is platform-aware.

How do I see which of these issues my Fly.io app has?

Run a VAS scan against your deployed Fly.io app URL. It checks every issue in the list above, confirms each by actually probing (not just reading headers), and prioritizes by severity with copy-paste fixes. Most Fly.io app scans return results in 2–3 minutes.