Headline
CVE-2023-49279: Stored XSS via SVG File Upload
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 all media from an different host (e.g cdn) than where Umbraco is hosted.
Package
nuget Umbraco.CMS (NuGet)
Affected versions
> 7.0.0
Patched versions
7.15.11, 8.18.9, 10.7.0, 11.5.0, 12.2.0+
Description
Impact
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.
Workaround
Implement the server side file validation
https://docs.umbraco.com/umbraco-cms/reference/security/serverside-file-validation
or
Serve all media from an different host (e.g cdn) that where umbraco is hosted
Related news
#### Impact 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. #### Workaround Implement the server side file validation https://docs.umbraco.com/umbraco-cms/reference/security/serverside-file-validation or Serve all media from an different host (e.g cdn) that where umbraco is hosted