Metro gates used by maintenance staff may have:

• Magnetic override ports
• IR triggers
• BLE test apps
• NFC developer modes

If such debug triggers are not secured or are hardcoded, tools like Flipper Zero can:

• Emulate NFC debug triggers
• Send “Open Gate” command in maintenance protocol

This leads to a gate opening without any valid ticket, just like what I observed.

This isn’t just a “cool trick” — it’s a critical infrastructure vulnerability.

• 💸 Revenue Leakage: Millions per year in unpaid entries
• 👤 Zero Traceability: Logs show “valid UID” but no ticket
• 🧑‍💻 Insider Abuse: Maintenance staff may leak tools/methods
• 🪧 No Deterrent: No alarms, no CCTV alerts, no logs
• 🧍‍♂️ Mass Exploitability: Tools easily available online

To avoid such UID-based or debug-based bypasses:

Solution Description ✅ Cryptographic Authentication Use DESFire EV2/EV3 with AES-based challenge 🔄 Dynamic UIDs / Session IDs Tokens should rotate UID or use session key 🧠 Gate-to-Server Sync Don’t make offline UID decisions 📡 Tamper Detection Alert on unknown debug/NFC tools 📊 Behavioral Monitoring Detect UID overuse or time-based patterns

I tried to report this through:

• Official metro feedback form
• Social media (DM to metro’s account)
• Customer helpline
• But — no concrete response yet.

⚠️ I did not clone or replay any UID myself.
I only observed behavior, researched tools, and documented the possibilities.

Most people think metro systems are “unhackable” because they’re physical.
But this case shows: if the software trust model is weak, physical access is meaningless.

What’s stopping someone from mass distributing pre-cloned UID tokens?
Or making an app that turns a phone into a metro entry bypass tool?

Nothing — if gate logic is weak.

👨‍💻 Aditya Sunny
Cybersecurity Enthusiast | Honoured by Bajaj Finance Security Heroes | Secured Meta (FB, IG, WA), Dell, Maffashion & more | Ex-Navodayan | Bug Hunter