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.
Metrics
Affected Vendors & Products
References
History
Wed, 11 Mar 2026 16:15:00 +0000
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ssvc
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Wed, 11 Mar 2026 12:00:00 +0000
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Umbraco
Umbraco cms |
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| Vendors & Products |
Umbraco
Umbraco cms |
Tue, 10 Mar 2026 22:00:00 +0000
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| Description | 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. | |
| Title | Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering | |
| Weaknesses | CWE-79 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-03-10T21:51:51.407Z
Updated: 2026-03-11T15:58:47.606Z
Reserved: 2026-03-09T17:41:56.077Z
Link: CVE-2026-31833
Updated: 2026-03-11T15:52:32.401Z
Status : Awaiting Analysis
Published: 2026-03-10T22:16:21.410
Modified: 2026-03-11T13:52:47.683
Link: CVE-2026-31833
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