---
id: CVE-2026-18115
title: >-
  Concrete CMS 9.2.0 to 9.5.2 did not enforce per-field edit_user_properties
  permissions on the REST API user write endpoints (PUT /ccm/api/1.0/users/{uID}
  and POST /ccm/api/1.0/users/{uID}/change_password)
summary: >-
  Concrete CMS 9.2.0 to 9.5.2 did not enforce per-field edit_user_properties
  permissions on the REST API user write endpoints (PUT /ccm/api/1.0/users/{uID}
  and POST /ccm/api/1.0/users/{uID}/change_password). A user with an
  update-scoped OA…
severity: high
cvss: 7.4
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-862
vendor: Concrete CMS
product: Concrete CMS
affected:
  - concrete_cms >= 9.2.0 <= 9.5.2
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:16:15.097'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-18115'
references:
  - url: >-
      https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes
    label: ff5b8ace-8b95-4078-9743-eac1ca5451de
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-15T19:18:00.746001Z'
cvssSource: cna
ingestedAt: '2026-09-15T18:41:59.139Z'
epss: 0.0026
epssPercentile: 0.18026
---

## Overview

Concrete CMS 9.2.0 to 9.5.2 did not enforce per-field edit_user_properties permissions on the REST API user write endpoints (PUT /ccm/api/1.0/users/{uID} and POST /ccm/api/1.0/users/{uID}/change_password). A user with an update-scoped OAuth token and permission to edit only one non-sensitive field could change another non-superuser's password, username, email, and attributes, taking over that account. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.4 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N. Thanks riodrwn for reporting.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.