What is the CVSS score of CVE-2026-31834?

CVE-2026-31834 has a CVSS 3.1 base score of 7.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

How to fix or mitigate CVE-2026-31834?

Within 24 hours: Inventory all Umbraco installations and verify version numbers; audit recent user group membership changes in backoffice logs for unauthorized privilege escalation attempts. Within 7 days: Implement network access controls restricting backoffice access to trusted IPs/VPNs; disable or restrict user management permissions for non-essential administrators pending patch availability. Within 30 days: Apply Umbraco security patches (16.5.1 or 17.2.2+) immediately upon release; conduct comprehensive backoffice permission audit and reset any suspicious administrative accounts.

Umbraco Cms CVE-2026-31834

Q: Which versions of Umbraco Cms are affected by CVE-2026-31834?

A privilege escalation vulnerability in Umbraco CMS allows authenticated backoffice users with user management permissions to illegally elevate their own privileges to administrator level,…. A patch is available.

HIGH

Improper Privilege Management (CWE-269)

2026-03-10 security-advisories@github.com

GHSA-rhcg-3h8r-v6vp

Privilege Escalation Umbraco Cms

7.2

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.2 HIGH

AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

Analysis Generated

Mar 12, 2026 - 21:55 vuln.today

CVE Published

Mar 10, 2026 - 22:16 nvd

HIGH 7.2

DescriptionGitHub Advisory

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.

AnalysisAI

Privilege escalation in Umbraco CMS versions 15.3.1 through 16.5.0 and 17.x before 17.2.2 allows authenticated backoffice users with user management permissions to assign themselves elevated privileges by bypassing authorization checks on role assignments. An attacker with these permissions could gain administrative access to the CMS without proper privilege validation. No patch is currently available for affected installations.

Technical ContextAI

This vulnerability (CWE-269: Improper Privilege Management) affects Umbraco is an ASP.NET CMS. From 15.3.1 to. 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 vulnerabi