CVE-2026-31833

MEDIUM EPSS 17.3%
Published Mar 10, 20263mo ago · Modified Mar 18, 20263mo ago
6.7 CVSS 3.1
Medium
Find Similar
Published Mar 10, 2026 3mo ago
Last Modified Mar 18, 2026 3mo ago

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.

CVSS Details

Base Score
6.7
Exploitability
1.2
Impact
5.5
Vector string
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L
Attack Vector Network
Attack Complexity Low
Privileges Required High
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability Low

Threat Intelligence

EPSS Exploit Probability
17.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-79 Cross-site Scripting Injection

Affected Products 2

VendorProductVersionRange
umbracoumbraco_cms*≥16.2.0  –  <16.5.1
umbracoumbraco_cms*≥17.0.0  –  <17.2.2

References 1

  • github.com https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-vrqc-59mw-qqg7
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.