Concrete CmsApplication · Concretecms

CVE-2023-28475

MEDIUM · 6.1 CVSS v3.1 Published 2023-04-28
Fix available
A fix is available. Upgrade to 9.2.0 or later.
See remediation →
68/100
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
Concrete CMS (previously concrete5) versions 8.5.12 and below, and versions 9.0 through 9.1.3 is vulnerable to Reflected XSS on the Reply form because msgID was not sanitized.

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 confidence

Reflected XSS vulnerability in Concrete CMS versions 8.5.12 and below, and 9.0-9.1.3. The msgID parameter in the Reply form is not properly sanitized before being reflected in the response, allowing injection of malicious scripts.

MitigationUpdate to a patched version of Concrete CMS that sanitizes the msgID parameter, or implement output encoding/validation on the msgID parameter in the Reply form handler.

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:< 9.2.0

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
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify Concrete CMS installation
    Locate the Concrete CMS installation directory. The version is typically defined in a version.php file at /concrete/config/version.php or in the root directory.
    Affected if Concrete CMS is installed on the system
  2. Determine installed version
    Open the version.php file and read the CMS version number defined in the version constants
    Affected if Installed version is below 9.2.0 (this includes all 8.x versions up to 8.5.12 and 9.0.x through 9.1.3)
  3. Check if Reply form is accessible
    Verify the messaging/reply form functionality is enabled. This can be done by checking if the file handling the reply form exists at /concrete/controllers/single_page/tools/required/messages.php or by attempting to access the messaging feature in the dashboard.
    Affected if The Reply form feature is enabled and accessible to users

Environment is affected if Concrete CMS version is below 9.2.0 AND the messaging Reply form feature is accessible, allowing the msgID parameter to be reflected without sanitization.

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.

dbcve · scoped
Upgrade available Upgrade to 9.2.0 or later
Fixed in 9.2.0
Interim mitigation

Update to a patched version of Concrete CMS that sanitizes the msgID parameter, or implement output encoding/validation on the msgID parameter in the Reply form handler.

Recommended fix High confidence

Concrete CMS 9.2.0

  1. Backup your current Concrete CMS installation and database before upgrading
  2. Download Concrete CMS version 9.2.0 from the official concretecms.com website
  3. Follow the standard Concrete CMS upgrade process: upload the new files, then navigate to /index.php/tools/required/upgrade or run the database upgrade script
  4. Verify that the msgID parameter on the Reply form is now properly sanitized
  5. Test that the XSS payload is no longer executed in the vulnerable parameter
Caveat Review the Concrete CMS 9.2.0 release notes for any features or configuration changes that may affect your site

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Concrete Cms Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

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dbcve dependency scanner

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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-2023-28475 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
  • No spam, self-promotion, credentials, or personal data