CVSS 4.0
2.3 lowCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:LCVE-2026-81921
Low (2.3) in concretecms concrete cms. EPSS 0.2% chance of exploitation in the next 30 days.
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.
Severity
CVSS 3.1
5.4 mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 14% of CVEs (scores of 2026-10-31)
- CWE
- CWE-862
- Published
- Modified
- Record from
- the NVD, synced
Affected
- concretecms:concrete_cms