CVE-2021-35959
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 · uneditedIn Plone 5.0 through 5.2.4, Editors are vulnerable to XSS in the folder contents view, if a Contributor has created a folder with a SCRIPT tag in the description field.
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 confidenceCross-site scripting (XSS) vulnerability in Plone 5.0-5.2.4's folder contents view allows a Contributor to embed a SCRIPT tag in a folder's description field, which then executes when an Editor views the folder contents.
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>= 5.0, <= 5.2.4CVSS 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
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/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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Determine installed Plone versionAccess the ZMI (Zope Management Interface) at /manage, navigate to portal_migration in the Zope root, or check the versions.py/buildout.cfg file in the Plone installation directory. Alternatively, use the command line: bin/instance -C version or check the Products.CMFPlone metadata.Affected if Installed version is >= 5.0 and <= 5.2.4
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Verify folder contents view is accessibleLog in as a Contributor or Editor user and navigate to any folder, then append /folder_contents to the URL or click the Contents tab to confirm the view loads.Affected if Folder contents view is accessible to users with Contributor or Editor roles
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Inspect folder description fields for script tagsAccess the ZMI at /manage, navigate to the portal (root folder), use the objectManager to list all objects, or query the database directly to inspect folder objects with description fields. Search for <script> tags within text in description fields.Affected if Any folder's description field contains unsanitized HTML including <script> tags that would execute when viewed in folder_contents
A user is affected if running Plone version 5.0 through 5.2.4 with unfiltered HTML enabled in folder descriptions and users have access to the folder contents view.
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 Plone to version 5.2.5 or later where this XSS vulnerability is patched. Alternatively, apply the official security patch and sanitize existing folder descriptions that may contain malicious SCRIPT tags.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-35959 — 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-2021-35959 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
- No spam, self-promotion, credentials, or personal data