CVE-2026-31834

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...

CVE-2026-31833

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...

CVE-2026-31834

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...

CVE-2026-31834

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...

CVE-2026-31834 Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks

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...

CVE-2026-31834

Umbraco CMS (ASP.NET) versions affected: 15.3.1 up to before 16.5.1 and 17.2.2. A privilege escalation vulnerability exists where authenticated backoffice users with permission to manage users may elevate privileges during modification of user group memberships due to insufficient authorization c...

CVE-2026-31834 Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks

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...

CVE-2026-31834 Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks

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...

CVE-2026-31833 Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering

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...

CVE-2026-31833 Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering

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...

CVE-2026-31833

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...

CVE-2026-31833 Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering

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...

CVE-2026-31833

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...

CVE-2026-31833

Summary : CVE-2026-31833 affects Umbraco (ASP.NET CMS). From 16.2.0 up to but not including 16.5.1 and 17.2.2, an authenticated backoffice user with Settings access can inject malicious HTML into property type descriptions due to an overly permissive attributeNameCheck in the UFM DOMPurify instan...

CVE-2026-31832

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by...

CVE-2026-31832 Umbraco Backoffice API Allows Unauthorized Modification of Domain Data

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by...

CVE-2026-31832 Umbraco Backoffice API Allows Unauthorized Modification of Domain Data

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by...

CVE-2026-31832

Umbraco (ASP.NET CMS) has a broken object-level authorization vulnerability in backoffice API endpoints affecting 14.0.0–before 16.5.1 and 17.2.2. An authenticated user can assign domain-related data to content nodes without proper authorization checks due to insufficient enforcement on the affec...

CVE-2026-31832 Umbraco Backoffice API Allows Unauthorized Modification of Domain Data

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by...

CVE-2026-31832

Umbraco is an ASP.NET CMS. From 14.0.0 to before 16.5.1 and 17.2.2, A broken object-level authorization vulnerability exists in a backoffice API endpoint that allows authenticated users to assign domain-related data to content nodes without proper authorization checks. The issue is caused by...