CVE-2026-8205
MEDIUMConcrete CMS 9.5.0 and below is vulnerable to authorization bypass in Calendar Block since action_get_events does not check canView on the calendar
Title source: cnaDescription
Concrete CMS 9.5.0 and below is vulnerable to authorization bypass in the Calendar Block since action_get_events does not check canView on the calendar which results in restricted event details being disclosed. 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 lalalala5678 for reporting.
References (1)
Core 1
Core References
Release Notes release-notes
https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes
Scores
CVSS v3
5.3
EPSS
0.0021
EPSS Percentile
11.3%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-425
Status
published
Products (2)
Concrete CMS/Concrete CMS
5.0 - 9.5.0
concretecms/concrete_cms
< 9.5.0
Published
May 21, 2026
Tracked Since
May 22, 2026