CVE-2019-6855
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 · uneditedIncorrect Authorization vulnerability exists in EcoStruxure Control Expert (all versions prior to 14.1 Hot Fix), Unity Pro (all versions), Modicon M340 (all versions prior to V3.20) , and Modicon M580 (all versions prior to V3.10), which could cause a bypass of the authentication process between EcoStruxure Control Expert and the M340 and M580 controllers.
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 · high confidenceThis is an incorrect authorization vulnerability in Schneider Electric's industrial control software that allows bypassing the authentication mechanism between EcoStruxure Control Expert/Unity Pro engineering workstations and Modicon M340/M580 PLC controllers. An attacker could potentially communicate with and manipulate the controllers without proper authentication.
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< 14.1= 14.1all versions< 3.10< 3.10< 3.10< 3.10< 3.10< 3.10CVSS 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
- Low
- Integrity
- Low
- Availability
- Low
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
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 checksWork through these to decide whether this CVE applies to you.
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Identify EcoStruxure Control Expert versionOpen EcoStruxure Control Expert, navigate to Help > About, or check the installed program version through Windows Programs and FeaturesAffected if The installed version is 14.1 or any version below 14.1
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Identify Unity Pro installationCheck for Unity Pro installation in Windows Programs and Features or look for Unity Pro executable in the installation directoryAffected if Unity Pro is installed (all versions are affected)
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Identify Modicon M580 PLC firmware versionConnect to the Modicon M580 PLC via EcoStruxure Control Expert or Unity Pro, navigate to the PLC properties or firmware information section, or access the PLC web interface if availableAffected if The PLC firmware version is below 3.10 for any of these models: Bmep584040, Bmeh584040, Bmep586040, Bmeh586040, Bmep581020, or Bmep582020
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Verify engineering workstation to PLC communication pathConfirm that the vulnerable engineering software (EcoStruxure Control Expert or Unity Pro) is configured to communicate with Modicon M340 or M580 PLCs over the networkAffected if The engineering software is being used to communicate with affected Modicon M340 or M580 PLCs without additional authentication controls in place
A user is affected if they have EcoStruxure Control Expert version 14.1 or below, any version of Unity Pro installed, or any Modicon M580 PLC with firmware below version 3.10, and these components are used together for engineering communications.
Generated from the published advisory. Verify against your own configuration.
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 data3.1014.1
Update EcoStruxure Control Expert to version 14.1 Hot Fix or later, update Modicon M340 firmware to V3.20 or later, and update Modicon M580 firmware to V3.10 or later. Apply within a scheduled maintenance window following change management procedures.
- Consultation4.0 h
- Implementation8.0 h
- Testing12.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,616.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2019-6855 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2019-6855 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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