CVE-2017-6027
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 · uneditedAn Arbitrary File Upload issue was discovered in 3S-Smart Software Solutions GmbH CODESYS Web Server. The following versions of CODESYS Web Server, part of the CODESYS WebVisu web browser visualization software, are affected: CODESYS Web Server Versions 2.3 and prior. A specially crafted web server request may allow the upload of arbitrary files (with a dangerous type) to the CODESYS Web Server without authorization which may allow remote code execution.
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 confidenceArbitrary file upload vulnerability in CODESYS Web Server versions 2.3 and prior allows unauthenticated attackers to upload files of dangerous types to the server, potentially achieving remote code execution.
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<= 2.3CVSS 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 checksWork through these to decide whether this CVE applies to you.
-
Identify CODESYS Web Server versionAccess the web server administration interface or check version information in the server configuration files or registry entries where CODESYS software stores version metadataAffected if The installed version is 2.3 or any version prior to 2.3
-
Confirm web server is runningCheck if the CODESYS Web Server service is active by querying running services or accessing the web server endpoint via browser on the configured port (typically port 80 or 8080)Affected if The web server is accessible and responding to requests
-
Check for file upload functionalityExamine the web server configuration files or web application files to identify if the file upload endpoint or functionality is enabled and accessible without authenticationAffected if File upload capability is present and accessible to unauthenticated users
-
Inspect web server directories for unexpected filesReview the directories served by the CODESYS Web Server (commonly the web root or upload directories) for any files with executable extensions such as .asp, .aspx, .php, .jsp, .exe, or .dll that were not deliberately placed thereAffected if Unexpected or suspicious files are found in the web server directories, particularly in locations accessible via HTTP
A system is affected if it runs CODESYS Web Server version 2.3 or earlier and has the web server enabled and exposed, with unauthenticated file upload access potentially available.
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 dataUpdate to a patched version of CODESYS Web Server when available; if no patch exists, restrict network access to the web server and implement web application firewall rules to block unauthorized file uploads.
- Consultation4.0 h
- Implementation2.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,872.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2017-6027 — 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-2017-6027 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
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.
- 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
- No spam, self-promotion, credentials, or personal data