VULNERABILITY INTELLIGENCE
CVE-2026-8204
CVSS score5.3 MEDIUM
EPSS probability0.21%
CISA KEVNot currently listed
Published2026-05-21
Last modified2026-07-23
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Description
Concrete CMS 9.5.0 and below is vulnerable to authorization Bypass in the Calendar Event Frontend Dialog which can allow cross-calendar data disclosure. A public calendar block can be used as a pivot point to access private calendar data. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.
Weakness classification
- ff5b8ace-8b95-4078-9743-eac1ca5451de: CWE-639
Primary references
- ff5b8ace-8b95-4078-9743-eac1ca5451de — Release Notes