CVE-2017-11666
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 · uneditedCross-site scripting (XSS) vulnerability in js/ViewerPanel.js in the file previewer plugin in Kopano WebApp versions 3.3.0 and earlier allows remote attackers to inject arbitrary web script or HTML via a specially crafted previewable file.
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 confidenceA stored Cross-Site Scripting (XSS) vulnerability exists in the file previewer plugin (js/ViewerPanel.js) of Kopano WebApp versions 3.3.0 and earlier. Attackers can inject malicious JavaScript or HTML by uploading a specially crafted previewable file; when other users view the file, the payload executes in their browser context.
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<= 3.3.0CVSS 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
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify Kopano WebApp versionLocate the version information for your Kopano WebApp installation. This is typically found in the WebApp's about page, in the package metadata, or in a version file within the WebApp directory structure.Affected if The installed version is 3.3.0 or any earlier version (e.g., 3.2.x, 3.1.x, etc.).
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Verify file previewer plugin is enabledCheck if the file previewer functionality (ViewerPanel) is active in your Kopano WebApp configuration. This plugin handles the preview of uploaded files in the web interface.Affected if The file previewer plugin is enabled and accessible to users.
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Confirm user file upload capabilityDetermine if users have the ability to upload files that can be previewed within the WebApp (e.g., documents, images, or other previewable file types).Affected if Users can upload and share files that trigger the preview functionality.
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Review browser-side XSS protectionsInspect the HTTP response headers from your Kopano WebApp server to check for Content Security Policy (CSP) headers or other XSS mitigation headers.Affected if No CSP headers or weak XSS protections are configured, allowing inline script execution.
You are affected if your Kopano WebApp version is 3.3.0 or earlier, the file previewer plugin is enabled, users can upload and preview files, and no strong CSP or XSS protections are in place.
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 dataUpgrade Kopano WebApp to a version newer than 3.3.0. Additionally, implement robust input validation and output encoding on the file preview content, and consider adding Content Security Policy (CSP) headers to mitigate XSS risks.
- Consultation2.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA3.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2017-11666 — 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-2017-11666 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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