CVE-2026-18121 Concrete CMS 9.5.2 and below is vulnerable to an authorization bypass (IDOR) in the Calendar block's frontend event dialog (/ccm/calendar/view_event/{bID}/{occurrence_id}).
| Reporter | Title | Published | Views | Family All 5 |
|---|---|---|---|---|
 | CVE-2026-18121 | 10 Sep 202623:10 | – | cve |
 | EUVD-2026-75885 | 11 Sep 202600:31 | – | euvd |
 | CVE-2026-18121 | 11 Sep 202600:17 | – | nvd |
 | PT-2026-89654 | 10 Sep 202600:00 | – | ptsecurity |
 | CVE-2026-18121 Concrete CMS 9.5.2 and below is vulnerable to an authorization bypass (IDOR) in the Calendar block's frontend event dialog (/ccm/calendar/view_event/{bID}/{occurrence_id}). | 10 Sep 202623:10 | – | vulnrichment |
[
{
"vendor": "Concrete CMS",
"product": "Concrete CMS",
"collectionURL": "https://github.com/concretecms/concretecms",
"repo": "https://github.com/concretecms/concretecms",
"versions": [
{
"status": "affected",
"version": "5.0.0",
"lessThanOrEqual": "9.5.2",
"versionType": "git"
}
],
"defaultStatus": "unaffected"
}
]| Source | Link |
|---|---|
| documentation | www.documentation.concretecms.org/developers/introduction/version-history/953-release-notes |
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10 Sep 2026 23:10Current
CVSS 46.3