Bmxnor0200 FirmwareOperating system · Schneider Electric

CVE-2018-7760

CRITICAL · 9.8 CVSS v3.0 Published 2018-04-18
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An authorization bypass vulnerability exists in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, BMXNOR0200. Requests to CGI functions allow malicious users to bypass authorization.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

An authorization bypass vulnerability in Schneider Electric's Modicon M340, Modicon Premium, Modicon Quantum PLC, and BMXNOR0200 allows malicious users to bypass authentication by sending requests directly to CGI functions, potentially granting unauthorized access to PLC management interfaces.

MitigationRestrict network access to PLC web interfaces using network segmentation, implement proper authorization enforcement on all CGI endpoints, and apply vendor-provided patches when released.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Bmxnor0200 FirmwareOperating system
Affected:all versions
Bmxnor0200h FirmwareOperating system
Affected:all versions
140cpu65150 FirmwareOperating system
Affected:all versions
140cpu31110 FirmwareOperating system
Affected:all versions
140cpu43412u FirmwareOperating system
Affected:all versions
140cpu65160 FirmwareOperating system
Affected:all versions
140cpu65260 FirmwareOperating system
Affected:all versions
140cpu65860 FirmwareOperating system
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the PLC model
    Check the device physical label, or query the PLC through the management interface or engineering workstation software to determine the exact model number (e.g., BMXNOR0200, 140cpu65150, etc.)
    Affected if The model matches one of the affected products: BMXNOR0200, BMXNOR0200h, 140cpu65150, 140cpu31110, 140cpu43412u, 140cpu65160, 140cpu65260, or 140cpu65860
  2. Confirm the firmware version
    Access the PLC web interface (if enabled) or use the engineering software to retrieve the firmware version information
    Affected if Any firmware version is installed, since the advisory states all versions are affected
  3. Verify the web interface is enabled
    Check the PLC network configuration through the engineering workstation or by attempting to reach the device IP on HTTP/HTTPS ports (typically ports 80/443 or 8080/8443)
    Affected if The web management interface is accessible on the network, which enables the CGI function attack surface
  4. Test CGI endpoint accessibility
    Send a direct HTTP request to a known CGI endpoint on the PLC (such as /cgi/bin/ or specific CGI scripts used for PLC management) without providing authentication credentials
    Affected if CGI endpoints respond without requiring authentication, indicating the authorization bypass is present
  5. Check network exposure of the PLC web interface
    Review firewall rules, network segmentation, and access control lists to determine if the PLC web management ports are reachable from untrusted network segments or the internet
    Affected if The PLC web interface is reachable from networks that should not have management access

A user is affected if they have any of the listed PLC models with the web interface enabled and exposed to networks where unauthorized CGI access is possible.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Restrict network access to PLC web interfaces using network segmentation, implement proper authorization enforcement on all CGI endpoints, and apply vendor-provided patches when released.

Fix this in Bmxnor0200 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,690
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2018-7760 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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