CVEvulnerability

CVE-2026-87031

2.1 LOW Published 2026-09-16 Modified 2026-09-21 Official page ↗
Status
Analyzed
Published
2026-09-16
Last modified
2026-09-21
Assigner
ff5b8ace-8b95-4078-9743-eac1ca5451de
CVSS 4.0 (ff5b8ace-8b95-4078-9743-eac1ca5451de)
2.1 LOW — CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
2.7 LOW — CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N
Weaknesses
CWE-862

Description

n Concrete CMS 9.2.0 through 9.5.3, the REST API user creation endpoint (POST /ccm/api/1.0/users, the add() method of concrete/src/Api/Controller/Users.php) did not perform a permission check before creating an account. As a result, any valid OAuth token carrying the users:add scope, including a client_credentials token with no associated user context, could create active, validated user accounts, bypassing email verification and administrator approval. Under default registration settings the created accounts could then edit page content, providing a path to stored cross-site scripting and further compromise. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.

Affected configurations

• concretecms concrete cms (>= 9.2.0 < 9.5.3)

Related

Weakness · CWE (1)

  • CWE-862 Missing Authorization weakness

References