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.

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.

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.

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.

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.

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.

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.

UmbracoIdentityExtensions is an Umbraco add-on package that enables easy extensibility points for ASP.Net Identity integration. In affected versions client secrets are not required which may expose some endpoints to untrusted actors. Since Umbraco is not a single-page application, the implicit flow is not safe. For traditional MVC applications, it is recommended to use the authorization code flow, which requires the client to authenticate with the authorization server using a client secret. This flow provides better security, as it involves exchanging an authorization code for an access token and/or ID token, rather than directly returning tokens in the URL fragment. This issue has been patched in commit `e792429f9` and a release to Nuget is pending. Users are advised to upgrade when possible.

Umbraco CMS 4.11.8 through 7.15.10, and 7.12.4, allows Remote Code Execution by authenticated administrators via msxsl:script in an xsltSelection to developer/Xslt/xsltVisualize.aspx.

File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a crafted web.config and asp file.