Concrete CmsApplication · Concretecms

CVE-2021-22949

MEDIUM · 5.4 CVSS v3.1 Published 2021-09-23
Fix available
A fix is available. Upgrade to after 8.5.5 or later.
See remediation →
61/100
Remediation priority · Elevated
Remotely reachable No privileges

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
A CSRF in Concrete CMS version 8.5.5 and below allows an attacker to duplicate files which can lead to UI inconvenience, and exhaustion of disk space.Credit for discovery: "Solar Security CMS Research Team"

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

A Cross-Site Request Forgery (CSRF) vulnerability in Concrete CMS versions 8.5.5 and below allows attackers to trick authenticated users into unknowingly triggering file duplication operations via forged requests. This can flood the CMS with duplicate files, causing UI/clutter issues and potentially exhausting available disk space.

MitigationImplement anti-CSRF token validation on all file manipulation operations including duplication, or upgrade to a patched version of Concrete 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
Concrete CmsApplication
Affected:<= 8.5.5

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
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
Low

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

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. Check Concrete CMS version
    Log into the CMS admin dashboard and navigate to Dashboard > System & Settings > Basics > Site Name, or check the version number in the footer of the admin pages. Alternatively, check the concrete/version.php file in the installation directory.
    Affected if The installed version is 8.5.5 or lower (any version up to and including 8.5.5).
  2. Verify file duplication feature exists
    Navigate to the File Manager in the CMS admin panel (Dashboard > Files > Files). Confirm that a duplicate or copy function is available for uploaded files.
    Affected if The file duplication feature is present and accessible to authenticated users.
  3. Inspect file duplication request for CSRF protection
    Use browser developer tools to intercept the HTTP request when duplicating a file. Check if the request includes a CSRF token parameter (often named 'ccm_token', 'csrf_token', or similar) in either the request body or headers.
    Affected if The duplication request does not require or validate a CSRF token.
  4. Check for duplicate files in the system
    In the File Manager, sort files by name or date to identify files with duplicate naming patterns (such as filename_copy, filename_1, etc.). Look for suspicious numbers of similar file names.
    Affected if A large number of duplicate files exist that were not intentionally uploaded by administrators.

A user is affected if their Concrete CMS installation is version 8.5.5 or below AND the file duplication feature is accessible without CSRF token validation.

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
Upgrade available Upgrade to a release after 8.5.5
Interim mitigation

Implement anti-CSRF token validation on all file manipulation operations including duplication, or upgrade to a patched version of Concrete CMS.

Fix this in Concrete Cms Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-22949 — 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-2021-22949 in production — separate from our analysis above.

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.

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
  • No spam, self-promotion, credentials, or personal data