Umbraco CMS up to 16.5.0/17.2.1 API Endpoint authorization

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in Umbraco CMS up to 16.5.0/17.2.1 and classified as problematic. This vulnerability affects unknown code of the component API Endpoint. Performing a manipulation results in authorization. This vulnerability is cataloged as CVE-2026-31832. It is possible to initiate the attack remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic has been found in Umbraco CMS up to 16.5.0/17.2.1. This affects an unknown part of the component API Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. This is going to have an impact on integrity, and availability. The summary by CVE is:

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 insufficient authorization enforcement on the affected API endpoint, whereby via an API call, domains can be set on content nodes that the editor does not have permission to access (either via user group privileges or start nodes). This vulnerability is fixed in 16.5.1 and 17.2.2.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-31832 since 03/09/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 16.5.1 or 17.2.0 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CMS 16.5.1/17.2.0

Timelineinfo

03/09/2026 CVE reserved
03/10/2026 +1 days VulDB entry created
03/11/2026 +0 days Advisory disclosed
03/16/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-fpvf-fvp5-996r
Status: Confirmed

CVE: CVE-2026-31832 (🔒)
GCVE (CVE): GCVE-0-2026-31832
GCVE (VulDB): GCVE-100-350199

Entryinfo

Created: 03/11/2026 00:05
Updated: 03/16/2026 07:27
Changes: 03/11/2026 00:05 (65), 03/16/2026 07:27 (1)
Complete: 🔍
Cache ID: 216::103

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