CVE-2026-18121
| Reporter | Title | Published | Views | Family All 8 |
|---|---|---|---|---|
 | 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 | – | cvelist |
 | EUVD-2026-75885 | 11 Sep 202600:31 | – | euvd |
 | CVE-2026-18121 | 10 Sep 202623:10 | – | mend |
 | CVE-2026-18121 | 11 Sep 202600:17 | – | nvd |
 | 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 | – | osv_cve |
 | PT-2026-89654 | 10 Sep 202600:00 | – | ptsecurity |
 | CVE-2026-18121: Missing Authorization | 11 Sep 202600:00 | – | rapid7 |
 | 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 |
| Parameter | Position | Path | Description | CWE |
|---|---|---|---|---|
| bID | path | /ccm/calendar/view_event/{bID}/{occurrence_id} | Authorization bypass (IDOR) in the calendar lightbox endpoint allows unauthenticated users to view event metadata by providing arbitrary sequential identifiers. | CWE-639, CWE-862 |
| occurrence_id | path | /ccm/calendar/view_event/{bID}/{occurrence_id} | Authorization bypass (IDOR) in the calendar lightbox endpoint allows unauthenticated users to view event metadata by providing arbitrary sequential identifiers. | CWE-639, CWE-862 |
Data
Build on a solid foundation with Vulners data
We provide the essential building blocks for cybersecurity solutions with comprehensive, structured, and constantly updated vulnerability and exploits data
Api
Power your application with Vulners API
The Vulners REST API offers reliable, high-performance access to vulnerability intelligence, with 99.9% SLA uptime and CDN-backed data delivery for seamless global access
App
Assess and manage vulnerabilities with Vulners tools
Built on top of Vulners' database and SDK, end-user solutions give security professionals and developers lightweight and powerful tools for vulnerability remediation
11 Sep 2026 15:17Current
6.1Medium risk
Vulners AI Score6.1
CVSS 46.3
EPSS0.00289
SSVC