CVE-2026-31833 (GCVE-0-2026-31833)
Vulnerability from cvelistv5
Published
2026-03-10 21:51
Modified
2026-03-11 15:58
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
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.
Impacted products
Vendor Product Version
umbraco Umbraco-CMS Version: >= 16.2.0, < 16.5.1
Version: >= 17.0.0, < 17.2.1
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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