Cross-site Scripting (XSS)Weakness · CWE-79

CVE-2026-4293

MEDIUM · 5.3 CVSS v3.1 Published 2026-05-20
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
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
The affected Kieback & Peter DDC building controllers are vulnerable to cross-site scripting, enabling JavaScript to be executed by the victim's browser, which allows the attacker to control the browser.

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

Kieback & Peter DDC building controllers contain a cross-site scripting vulnerability in their web interface. Attackers can inject malicious JavaScript that executes in victims' browsers, enabling session hijacking, credential theft, or further malicious actions against users accessing the compromised controller interface.

MitigationImplement input validation and output encoding on all user-supplied data in the web interface, apply vendor-provided firmware updates, and configure Content Security Policy headers to restrict script execution.

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

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
None
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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. Confirm the Kieback & Peter DDC web interface is accessible
    Access the web interface by navigating to the controller's IP address or hostname over HTTP/HTTPS in a browser. Verify the login page or dashboard loads successfully.
    Affected if The web interface is publicly or internally accessible on the network.
  2. Verify the product is a Kieback & Peter DDC controller
    Check the web interface login page, banner, or system information page for the product name and firmware version. Compare the firmware version against any known version ranges for this device.
    Affected if The device is a Kieback & Peter DDC building controller with a known or unknown firmware version.
  3. Identify unauthenticated access to the web interface
    Attempt to access protected pages or functionality without logging in. Check if the application permits access to input fields or pages without authentication.
    Affected if The web interface permits unauthenticated access to input fields where malicious scripts could be injected.
  4. Locate input fields that accept user-supplied data
    Log in to the web interface and navigate through configuration pages, device naming fields, scheduling inputs, or any form that accepts text input. Inspect the HTML source to see if input is reflected in the response without encoding.
    Affected if The web interface contains input fields that render user-supplied data back to the page without visible sanitization.
  5. Test for reflected input without encoding
    Enter a test string containing HTML or JavaScript characters (such as <script>alert(1)</script> or <img src=x onerror=alert(1)>) into identified input fields and save or submit the form. Then view the page or revisit the field to see if the raw characters are rendered.
    Affected if The submitted test string is rendered as executable HTML or JavaScript rather than being escaped or stripped.

You are affected if the Kieback & Peter DDC web interface is enabled and any user-supplied input fields in the interface reflect unsanitized data back as executable HTML or JavaScript.

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

Implement input validation and output encoding on all user-supplied data in the web interface, apply vendor-provided firmware updates, and configure Content Security Policy headers to restrict script execution.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-4293 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-4293 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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