Os LoaderApplication · Schneider Electric

CVE-2020-7498

CRITICAL · 9.8 CVSS v3.1 Published 2020-06-16
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
A CWE-798: Use of Hard-coded Credentials vulnerability exists in the Unity Loader and OS Loader Software (all versions). The fixed credentials are used to simplify file transfer. Today the use of fixed credentials is considered a vulnerability, which could cause unauthorized access to the file transfer service provided by the Modicon PLCs. This could result in various unintended results.

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 confidence

CVE-2020-7498 is a hardcoded credentials vulnerability (CWE-798) affecting Unity Loader and OS Loader Software used with Modicon PLCs. The software contains embedded, fixed credentials used for file transfer services, which can be exploited by attackers to gain unauthorized access to the PLC file transfer functionality.

MitigationRemove or change hardcoded credentials, implement proper authentication mechanisms, and apply any available vendor patches. Consider network segmentation to limit exposure of file transfer services until remediation is complete.

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
Os LoaderApplication
Affected:all versions
Unity LoaderApplication
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:3.1/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 if Unity Loader or Os Loader is installed
    Check for installed Schneider Electric PLC loader software by reviewing installed programs list in Control Panel, or search for executable files named 'UnityLoader.exe' or 'OsLoader.exe' in typical installation directories such as C:\Program Files\Schneider Electric\ or C:\Program Files (x86)\Schneider Electric\
    Affected if Either Unity Loader or Os Loader software is present on the system
  2. Locate file transfer service configuration
    Examine the loader software configuration directory for files related to file transfer services, commonly named 'FTPServer.ini', 'TransferConfig.xml', or similar configuration files that control the built-in file transfer functionality
    Affected if File transfer service configuration files exist and the service is enabled (not explicitly disabled)
  3. Inspect for embedded credentials in configuration
    Open and review the identified configuration files using a text editor, looking for fields containing hardcoded username and password values such as 'user=', 'password=', 'passwd=', or 'credentials='
    Affected if Plaintext or encoded hardcoded credentials are found in configuration files associated with file transfer services
  4. Verify network exposure of file transfer ports
    Run 'netstat -an' or use a network port scanner to check if the loader file transfer service ports (typically FTP/TCP ports 20/21 or custom ports used by Schneider loaders) are listening on network interfaces accessible from non-localhost addresses
    Affected if File transfer service ports are listening on external-facing network interfaces (0.0.0.0 or non-private IP addresses)

A defender is affected if Schneider Electric Unity Loader or Os Loader software is installed and the file transfer service with hardcoded credentials is enabled and network-accessible.

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

Remove or change hardcoded credentials, implement proper authentication mechanisms, and apply any available vendor patches. Consider network segmentation to limit exposure of file transfer services until remediation is complete.

Fix this in Os Loader Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing8.0 h
  • Review / QA4.0 h
36.0 hours of engineering $6,400
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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-2020-7498 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
  • No weaponised exploit code, or anything meant to cause harm
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