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-2026-31834 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 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-2026-31833 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

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-2026-31833 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-2026-31832 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 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...

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...

PT-2026-24486

Name of the Vulnerable Software and Affected Versions Umbraco versions 16.2.0 through 16.5.0 Umbraco version 17.2.2 Description Umbraco is an ASP.NET CMS. An authenticated backoffice user with access to Settings can inject malicious HTML into property type descriptions. The issue stems from an...

PT-2026-24485

Name of the Vulnerable Software and Affected Versions Umbraco versions 14.0.0 through 16.5.0 Umbraco version 17.2.2 Description Umbraco, an ASP.NET CMS, contains a flaw in a backoffice API endpoint related to object-level authorization. Authenticated users can assign domain-related data to conten...

CVE-2026-31833: Improper Neutralization of Input During Web Page Generation

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-2026-31832: Authorization Bypass Through User-Controlled Key

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...

PT-2026-24487

Name of the Vulnerable Software and Affected Versions Umbraco versions 15.3.1 through 16.5.0 Umbraco version 17.2.2 Description Umbraco CMS contains a privilege escalation issue. Authenticated backoffice users with user management permissions may be able to gain elevated privileges due to...