---
type: concept
tags: [parking, security, access-control, protocol]
sources: [parking-system-architecture]
updated: 2026-06-14
---

# UHPPOTE UDP Protocol (the weakness)

The [[uhppote-controller]] communicates over **UDP port 60000 with no authentication and no
encryption**. Anyone who can place a packet on that LAN can send an "open" command to any door.
This is *the* security issue — not safety (safety is the barrier operator's, per
[[barrier-not-a-door]]). (See [[parking-system-architecture]] §6.)

**Mitigation: [[network-isolation]] is mandatory.** The security boundary is the network because
it cannot be the device.

## Why you can't fix it in firmware

The open-source `uhppoted` ecosystem is **protocol reverse-engineering only** — clients speaking
the existing UDP protocol. No source, SDK, schematic, or toolchain to build/flash custom
firmware. The controller accepts only the **manufacturer's official** firmware images. You
cannot configure or patch your way to authentication on this hardware.

## Unauthenticated commands that undermine the log

The record-level log is append-only, but these don't touch individual records:

| Vector | Command | Effect |
| --- | --- | --- |
| Blinding | `record-special-events false` | Stops logging door events going forward |
| Wipe | `restore-default-parameters` | Factory reset — clears config + event state |
| Rollover | (generate events / fall behind) | Finite circular buffer; old events overwritten |
| Time skew | `set-time` | Corrupts / backdates timestamps |
| Index desync | `set-event-index` | Moves the retrieval pointer; naive ingestion skips events |

The defensive response is [[event-log-ingestion]]. The preventive alternative is the
[[esp32-custom-controller]].