Umbraco Cms

Umbraco is an ASP.NET CMS. From 15.3.1 to before 16.5.1 and 17.2.2, A privilege escalation vulnerability has been identified in Umbraco CMS. Under certain conditions, authenticated backoffice users with permission to manage users, may be able to elevate their privileges due to insufficient authorization enforcement when modifying user group memberships. The affected functionality does not properly validate whether a user has sufficient privileges to assign highly privileged roles. This vulnerability is fixed in 16.5.1 and 17.2.2.

Published: 2026-03-10T21:53:49.153Z
Updated: 2026-03-11T15:58:38.854Z

Umbraco is an ASP.NET CMS. From 16.2.0 to before 16.5.1 and 17.2.2, An authenticated backoffice user with access to Settings can inject malicious HTML into property type descriptions. Due to an overly permissive attributeNameCheck configuration (/.+/) in the UFM DOMPurify instance, event handler attributes such as onclick and onload, when used within Umbraco web components (umb-*, uui-*, ufm-*) were not filtered. This vulnerability is fixed in 16.5.1 and 17.2.2.

Published: 2026-03-10T21:51:51.407Z
Updated: 2026-03-11T15:58:47.606Z

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by insufficient authorization enforcement on the affected API endpoint, whereby via an API call, domains can be set on content nodes that the editor does not have permission to access (either via user group privileges or start nodes). This vulnerability is fixed in 16.5.1 and 17.2.2.

Published: 2026-03-10T21:49:54.908Z
Updated: 2026-03-11T15:58:54.874Z

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. In certain configurations, incomplete clean-up of temporary upload files may additionally expose the NTLM hash of the Windows account running the Umbraco application. This issue is fixed in version 13.12.1.

Published: 2025-12-09T20:09:27.054Z
Updated: 2025-12-12T20:33:09.177Z

Umbraco is an ASP.NET CMS. In versions 13.0.0 through 13.9.2, 15.0.0 through 15.4.1 and 16.0.0 through 16.1.0, the content delivery API can be restricted from public access where an API key must be provided in a header to authorize the request. It's also possible to configure output caching, such that the delivery API outputs will be cached for a period of time, improving performance. There's an issue when these two things are used together, where caching doesn't vary by the header that contains the API key. As such, it's possible for a user without a valid API key to retrieve a response for a given path and query if it has recently been requested and cached by request with a valid key. This is fixed in versions 13.9.3, 15.4.4 and 16.1.1.

Published: 2025-07-30T13:41:07.799Z
Updated: 2025-07-30T14:06:12.115Z