Joomla\!Application · Joomla
CVE-2021-26033
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 issue was discovered in Joomla! 3.0.0 through 3.9.26. A missing token check causes a CSRF vulnerability in the AJAX reordering endpoint.
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 CSRF vulnerability exists in Joomla! versions 3.0.0 through 3.9.26 due to a missing token check in the AJAX reordering endpoint. An attacker could craft a malicious request that tricks an authenticated administrator into unknowingly performing reorder actions on the CMS.
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
Joomla\!Application
>= 3.0.0, <= 3.9.26CVSS 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
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/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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Check installed Joomla versionAccess the Joomla administrator backend or check version file (typically /administrator/manifests/files_joomla.xml or the system information page)Affected if Installed version is 3.0.0 through 3.9.26 inclusive
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Verify AJAX reordering endpoint is accessibleConfirm the site's administrator interface includes article or content reordering functionality (typically through com_content or similar component)Affected if The AJAX reordering feature is available and accessible to administrators
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Confirm administrator session handlingReview authentication configuration and session management settings in Joomla's global configurationAffected if Administrators can authenticate and maintain active sessions on the affected site
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Determine if site uses Joomla's reorder functionalityInspect whether the CMS is actively using features that trigger the AJAX reorder endpoint (such as managing articles, categories, or custom content ordering)Affected if The site utilizes content management features that invoke the vulnerable reorder endpoint
A site is affected if it runs Joomla version 3.0.0 through 3.9.26 and has an authenticated administrator session with access to content reordering functionality that triggers the vulnerable AJAX endpoint.
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 dataImplement CSRF token validation (JSession::checkToken) in the AJAX reordering endpoint and ensure all state-changing requests require valid token verification.
Fix this in Joomla\!
Scoped from the published advisory
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-26033 — 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-2021-26033 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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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