Umbraco CMS 12
Umbraco CMS 12
The Umbraco CMS 12 reached end of service life on Jun 29, 2024 — Umbraco CMS no longer ships security patches or fixes for it. Our third-party support keeps it safe to run: 24/7 engineers manage issues, remediate vulnerabilities, and help you maintain compliance.
24/7 engineers own your Umbraco CMS 12 incidents end to end.
Mitigation and patch-around guidance when the vendor no longer ships fixes.
Controls evidence and documentation that keep auditors satisfied.
Specifications
- product
- umbraco
- release
- 12
- product Label
- Umbraco CMS
- release Label
- 12
- codename
- lts
- latest Version
- 12.3.10
- release Date
- 2023-06-29
- maintained
- source Url
- https://endoflife.date/umbraco
Lifecycle Dates
- End of Service Life
- Jun 29, 2024
- Last OEM Support
- Mar 29, 2024
OEM vs. 3rd Party Support
See how third-party support compares to the vendor contract for Umbraco CMS 12 — monitoring, break/fix, vulnerability work, operations and compliance, before and after EOSL.
| Feature | OEM Support | 3rd Party Support |
|---|---|---|
| Post-EOSL Support | ||
| Break/Fix Support | Until EOSL | |
| 24/7 Monitoring | ||
| Vulnerability Scanning & Remediation | ||
| Managed Operations | ||
| Procedure & Configuration Review | ||
| Compliance & Audit Documentation | Limited | |
| Discounted Migration to Other Platforms |
Why Choose 3rd Party Support for Umbraco CMS 12?
Vulnerability Remediation
Scanning, mitigation and patch-around guidance for Umbraco CMS 12 when the vendor no longer ships fixes.
Compliance Maintenance
Procedure review, controls evidence and the documentation auditors ask for — maintained continuously, not scrambled at audit time.
24/7 Expert Support
Engineers who know this release monitor, manage and fix issues around the clock — break/fix to managed operations.
Umbraco CMS 12 Support: Frequently Asked Questions
Is the Umbraco CMS 12 still supported?
Umbraco CMS ended support for the Umbraco CMS 12 on Jun 29, 2024 — no more patches or fixes from the vendor. Third-party support keeps it covered: our engineers manage issues, remediate vulnerabilities, and help you maintain compliance for as long as you run it.
When is the Umbraco CMS 12 end of service life (EOSL) date?
Umbraco CMS lists the end of service life for the Umbraco CMS 12 as Jun 29, 2024.
Can I keep using the Umbraco CMS 12 after its EOSL date?
Yes. EOSL means Umbraco CMS stops issuing patches and support — the software itself keeps running. Third-party support covers it from there: issue management, security vulnerability remediation, and the compliance documentation auditors ask for, for as long as you choose to run it.
How much does third-party support for the Umbraco CMS 12 cost?
Typically 40-70% below the OEM maintenance renewal price. Exact pricing depends on quantity, service level and location — request a quote and we respond within 24 hours.
Known Vulnerabilities Affecting Umbraco CMS 12
17 published CVEs affect the Umbraco CMS 12, including 2 rated critical or high severity. Umbraco CMS no longer ships security patches for this release — our engineers provide mitigation guidance, workarounds and hardening support.
| CVE | Severity | CVSS | Published | Summary |
|---|---|---|---|---|
| CVE-2023-49089 | HIGH | 7.7 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.0, Backoffice users with permissions to create packages can use path traversal and thereby write outside of the expected location. Versions 8.18.10, 10.8.1, and 12.3.0 contain a patch for this issue. |
| CVE-2023-37267 | HIGH | 7.5 | Jul 13, 2023 | Umbraco is a ASP.NET CMS. Under rare conditions a restart of Umbraco can allow unauthorized users access to admin-level permissions. This vulnerability was patched in versions 10.6.1, 11.4.2 and 12.0.1. |
| CVE-2024-10761 | MEDIUM | 6.9 | Nov 4, 2024 | A vulnerability was found in Umbraco CMS up to 10.7.7/12.3.6/13.5.2/14.3.1/15.1.1. It has been classified as problematic. Affected is an unknown function of the file /Umbraco/preview/frame?id{} of the component Dashboard. The manipulation of the argument culture leads to cross site scripting. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 10.8.8, 13.5.3, 14.3.2 and 15.1.2 is able to address this issue. It is recomm |
| CVE-2024-34071 | MEDIUM | 6.1 | May 21, 2024 | Umbraco is an ASP.NET CMS used by more than 730.000 websites. Umbraco has an endpoint that is vulnerable to open redirects. The endpoint is protected so it requires the user to be signed into backoffice before the vulnerable is exposed. This vulnerability has been patched in version(s) 8.18.14, 10.8.6, 12.3.10 and 13.3.1. |
| CVE-2026-46616 | MEDIUM | 5.4 | Jun 10, 2026 | Umbraco is an ASP.NET CMS. Prior to versions 13.14.0 and 17.4.0, some of the Surface Controllers in the CMS provide to support member related operations fail to validate redirect URLs, making Razor templates that derive 'RedirectUrl' from user-controlled query parameters vulnerable to malicious redirect attacks. This issue has been patched in versions 13.14.0 and 17.4.0. |
| CVE-2023-49273 | MEDIUM | 5.4 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.4, users with low privileges (Editor, etc.) are able to access some unintended endpoints. Versions 8.18.10, 10.8.1, and 12.3.4 contain a patch for this issue. |
| CVE-2025-46736 | MEDIUM | 5.3 | May 6, 2025 | Umbraco is a free and open source .NET content management system. Prior to versions 10.8.10 and 13.8.1, based on an analysis of the timing of post login API responses, it's possible to determine whether an account exists. The issue is patched in versions 10.8.10 and 13.8.1. No known workarounds are available. |
| CVE-2023-49278 | MEDIUM | 5.3 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.4, a brute force exploit can be used to collect valid usernames. Versions 8.18.10, 10.8.1, and 12.3.4 contain a patch for this issue. |
| CVE-2025-66625 | MEDIUM | 4.9 | Dec 9, 2025 | Umbraco is an ASP.NET CMS. Due to unsafe handling and deletion of temporary files in versions 10.0.0 through 13.12.0, during the dictionary upload process an attacker with access to the backoffice can trigger predictable requests to temporary file paths. The application’s error responses (HTTP 500 when a file exists, 404 when it does not) allow the attacker to enumerate the existence of arbitrary files on the server’s filesystem. This vulnerability does not allow reading or writing file contents |
| CVE-2025-27602 | MEDIUM | 4.9 | Mar 11, 2025 | Umbraco is a free and open source .NET content management system. In versions of Umbraco's web backoffice program prior to versions 10.8.9 and 13.7.1, via manipulation of backoffice API URLs, it's possible for authenticated backoffice users to retrieve or delete content or media held within folders the editor does not have access to. The issue is patched in versions 10.8.9 and 13.7.1. No known workarounds are available. |
| CVE-2025-27601 | MEDIUM | 4.3 | Mar 11, 2025 | Umbraco is a free and open source .NET content management system. An improper API access control issue has been identified Umbraco's API management package prior to versions 15.2.3 and 14.3.3, allowing low-privilege, authenticated users to create and update data type information that should be restricted to users with access to the settings section. The issue is patched in versions 15.2.3 and 14.3.3. No known workarounds are available. |
| CVE-2023-48313 | MEDIUM | 4.3 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in 10.0.0 and prior to versions 10.8.1 and 12.3.4, Umbraco contains a cross-site scripting (XSS) vulnerability enabling attackers to bring malicious content into a website or application. Versions 10.8.1 and 12.3.4 contain a patch for this issue. |
| CVE-2023-48227 | MEDIUM | 4.3 | Dec 12, 2023 | 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 12.3.0, Backoffice users with send for approval permission but not publish permission are able to publish in some scenarios. Versions 8.18.10, 10.7.0, and 12.3.0 contains a patch for this issue. No known workarounds are available. |
| CVE-2024-35218 | MEDIUM | 4.2 | May 21, 2024 | Umbraco CMS is an ASP.NET CMS used by more than 730.000 websites. Stored Cross-site scripting (XSS) enable attackers that have access to backoffice to bring malicious content into a website or application. This vulnerability has been patched in version(s) 8.18.13, 10.8.4, 12.3.7, 13.1.1 by implementing IHtmlSanitizer. |
| CVE-2023-49279 | LOW | 3.7 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in version 7.0.0 and prior to versions 7.15.11, 8.18.9, 10.7.0, 11.5.0, and 12.2.0, a user with access to the backoffice can upload SVG files that include scripts. If the user can trick another user to load the media directly in a browser, the scripts can be executed. Versions 7.15.11, 8.18.9, 10.7.0, 11.5.0, and 12.2.0 contain a patch for this issue. Some workarounds are available. Implement the server side file validation or serve |
| CVE-2023-49274 | LOW | 3.7 | Dec 12, 2023 | Umbraco is an ASP.NET content management system (CMS). Starting in version 8.0.0 and prior to versions 8.18.10, 10.8.1, and 12.3.4, a user enumeration attack is possible when SMTP is not set up correctly, but reset password is enabled. Versions 8.18.10, 10.8.1, and 12.3.4 contain a patch for this issue. |
| CVE-2023-38694 | LOW | 3.5 | Dec 12, 2023 | 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. |