CVE-2026-18116highCWE-79

CVE-2026-18116: fallo de gravedad alta en Concrete CMS

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

Publicada el · Actualizada el

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41Vexday Risk Score

Sin señal de explotación. Ella tiene prueba de concepto pública.

ssvc Attendcvss 7.3epss 0.3%
de la publicación al arma30 días
Publicada en NVD14 sept
1ª PoC+30d
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.
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
Productos afectados
Concrete CMS · Concrete CMS
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