cvedb.io
CVE-2026-8204
MEDIUM · CVSS 5.3
EPSS exploitation probability: 0%
Published 2026-05-21T21:16:33.530 · Last modified 2026-06-17T11:03:37.980

Summary

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.

Affected products

concretecms — concrete_cms

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.