Umbraco CmsApplication · Umbraco

CVE-2023-38694

MEDIUM · 5.4 CVSS v3.1 Published 2023-12-12
Fix available
A fix is available. Upgrade to 8.18.10 / 10.7.0 or later.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

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
Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.7.0, and 12.1.0, a user with access to a specific part of the backoffice is able to inject HTML code into a form where it is not intended. Versions 8.18.10, 10.7.0, and 12.1.0 contain a patch for this issue.

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

Umbraco CMS versions 8.0.0 through 8.18.10, 10.7.0, and 12.1.0 contain an HTML injection vulnerability in a backoffice form. An authenticated user with access to a specific area of the backoffice can inject arbitrary HTML code into a form field where HTML input is not intended, potentially leading to stored HTML injection attacks.

MitigationUpgrade Umbraco to version 8.18.10, 10.7.0, or 12.1.0 or later. Alternatively, restrict backoffice access to only trusted administrators until the upgrade can be applied.

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
Umbraco CmsApplication
Affected:>= 8.0.0, < 8.18.10>= 9.0.0, < 10.7.0>= 11.0.0, < 12.1.0

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
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 checks

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

  1. Identify Umbraco CMS version
    Check the installed Umbraco version by reviewing the assembly version of Umbraco.Core.dll in the /bin folder, or look for the version in the website's footer in the backoffice login page, or check the umbraco-config.xml/manifest file if present
    Affected if The installed version falls within 8.0.0 to 8.18.9, 9.0.0 to 10.6.x, or 11.0.0 to 12.0.x (i.e., less than 8.18.10, 10.7.0, or 12.1.0)
  2. Confirm backoffice access exists
    Verify that user accounts exist with access to the Umbraco backoffice by checking the Users section in the backoffice or reviewing the database Users table for active accounts
    Affected if Any authenticated user account exists with backoffice access
  3. Locate the vulnerable form area
    Navigate to the backoffice area containing the affected form field; this vulnerability exists in a backoffice form where HTML input is not expected - check areas like member forms, content templates, or settings forms depending on your installation
    Affected if A backoffice user with access to the specific form can input data into fields not intended for HTML content

You are affected if your Umbraco installation version is less than 8.18.10, 10.7.0, or 12.1.0 AND any authenticated user has access to the backoffice area containing the vulnerable form field.

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 8.18.10 / 10.7.0 / 12.1.0 or later
Fixed in 8.18.1010.7.012.1.0
Interim mitigation

Upgrade Umbraco to version 8.18.10, 10.7.0, or 12.1.0 or later. Alternatively, restrict backoffice access to only trusted administrators until the upgrade can be applied.

Recommended fix High confidence

Upgrade to Umbraco 8.18.10 (for v8.x), 10.7.0 (for v9/v10.x), or 12.1.0 (for v11/v12.x) depending on your branch

  1. 1. Identify the current Umbraco version by checking the project files or the Umbraco backoffice (Help > About)
  2. 2. Determine which version branch your installation belongs to (v8, v9/v10, or v11/v12)
  3. 3. For Umbraco 8.x (versions 8.0.0 to 8.18.9): Upgrade to version 8.18.10 or later
  4. 4. For Umbraco 9.x/10.x (versions 9.0.0 to 10.6.x): Upgrade to version 10.7.0 or later
  5. 5. For Umbraco 11.x (versions 11.0.0 to 12.0.x): Upgrade to version 12.1.0 or later
  6. 6. Before upgrading, review the release notes for the target version for any breaking changes
  7. 7. Perform the upgrade using NuGet package manager: Update-Package Umbraco.Cms -Version <target-version>
  8. 8. Test the upgrade in a non-production environment before deploying to production

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

Fix this in Umbraco Cms Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,080
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,328.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-38694 — 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-2023-38694 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