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.
CVE-2018-5400
CRITICALNVD 9.19.1—
EchelonGraph scoreMEDIUM confidence
Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2022-05-13. NVD baseline CVSS 9.1; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.1Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 9.1
- EG Score
- 9.1(medium)
- EG Risk
- 46(Track)EG Risk 46/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity91% × 45%Exploitation1% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 52%
- KEV
- Not listed
Published
October 8, 2018
Last Modified
November 21, 2024
Advisory Details (2)
Auto-updated Jul 20, 2026No patch confirmed yet. Sources: cert.
generic
Auto-Maskin RP210E, DCU210E, and Marine Observer Pro (Android App) | CISA
https://www.us-cert.gov/ics/advisories/icsa-20-051-04cert
VU#176301 - Auto-Maskin DCU 210E RP 210E and Marine Pro Observer App
https://www.kb.cert.org/vuls/id/176301Frequently asked(5)
What is CVE-2018-5400?
CVE-2018-5400 is a critical vulnerability published on October 8, 2018. 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…
When was CVE-2018-5400 disclosed?
CVE-2018-5400 was first published in the National Vulnerability Database on October 8, 2018, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2018-5400 actively exploited?
CVE-2018-5400 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 47.6% of all scored CVEs.
What is the CVSS score of CVE-2018-5400?
CVE-2018-5400 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2018-5400?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2018-5400, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2018-5400
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