CVE-2026-18116

See a problem?
Please try reporting it to the source first.

Source

https://cve.org/CVERecord?id=CVE-2026-18116

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18116.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-18116

Published

2026-09-14T22:05:49Z

Modified

2026-09-17T03:30:26Z

Severity

7.3 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N CVSS Calculator

Summary

Concrete CMS 8.3.0 to 9.5.2 is vulnerable to Stored XSS in Calendar Event Name via Workflow Approval Notifications

Details

Concrete CMS 8.3.0 to 9.5.2 stored calendar event names without sanitization and rendered them without HTML escaping in the workflow approval and deletion notifications shown in the dashboard "Waiting For Me" block. A registered user permitted to add events to a calendar governed by an approval workflow could submit an event whose name contained a script payload, which then executed in an administrator's browser when the pending request was displayed and could be used to create a new administrator account. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks v01demort for reporting.

Database specific

{
    "cna_assigner": "ConcreteCMS",
    "cwe_ids": [
        "CWE-79"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18116.json"
}

References

Affected packages

Git / github.com/concretecms/concretecms

Affected ranges

Type

GIT

Repo

https://github.com/concretecms/concretecms

Events

Introduced

42e323aa14b5efdc3a75594bf02faec26ebb35cd

Last Affected

8fe9708072c3815a5df719b592e4b23b43b4ff7a

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "8.3.0"
        },
        {
            "last_affected": "9.5.2"
        }
    ],
    "source": "AFFECTED_FIELD"
}

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18116.json"