Description
Umbraco is an ASP.NET CMS. From 15.3.1 to before 16.5.1 and 17.2.2, A privilege escalation vulnerability has been identified in Umbraco CMS. Under certain conditions, authenticated backoffice users with permission to manage users, may be able to elevate their privileges due to insufficient authorization enforcement when modifying user group memberships. The affected functionality does not properly validate whether a user has sufficient privileges to assign highly privileged roles. This vulnerability is fixed in 16.5.1 and 17.2.2.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Attack Vector
- network
- Complexity
- low
- Privileges
- high
- User Action
- none
- Scope
- unchanged
- Confidentiality
- high
- Integrity
- high
- Availability
- high
- Weaknesses
- CWE-269CWE-284CWE-862
Metadata
- Primary Vendor
- UMBRACO
- Published
- 3/10/2026
- Last Modified
- 3/18/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
umbraco : umbraco_cmsumbraco : umbraco_cms
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