CVEvulnerability

CVE-2026-81921

2.3 LOW Published 2026-09-15 Modified 2026-09-18 Official page ↗
Status
Analyzed
Published
2026-09-15
Last modified
2026-09-18
Assigner
ff5b8ace-8b95-4078-9743-eac1ca5451de
CVSS 4.0 (ff5b8ace-8b95-4078-9743-eac1ca5451de)
2.3 LOW — CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/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])
5.4 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Weaknesses
CWE-862

Description

Concrete CMS 8.5.3 through 9.5.2 enabled the OAuth 2.0 refresh-token grant using the unmodified upstream League grant, which issued new access tokens from a valid refresh token without re-checking the associated account's active status. A user who obtained a refresh token while active could therefore continue to mint valid access tokens after being deactivated or suspended (uIsActive=0), so deactivating an account did not revoke its API access. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L. Thanks sh4d0byss for reporting.

Affected configurations

• concretecms concrete cms (>= 8.5.3 < 9.5.3)

Related

Weakness · CWE (1)

  • CWE-862 Missing Authorization weakness

References