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In Concrete CMS 9.5.0 and below, the RSS Displayer block accepts a feed URL from any page editor and fetches it server-side without validation enabling redirect-to-internal bypasses. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.1 with a vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:N.
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Title: Concrete CMS, Description: En Concrete CMS 9.5.0 y versiones inferiores, el bloque RSS Displayer acepta una URL de feed de cualquier editor de página y la obtiene del lado del servidor sin validación, lo que permite eludir las redirecciones internas. El equipo de seguridad de Concrete CMS asignó a esta vulnerabilidad una puntuación CVSS v.4.0 de 2.1 con un vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:N.
New CVE Received from ConcreteCMS5/21/2026 6:16:49 PM
Action
Type
Old Value
New Value
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Description
In Concrete CMS 9.5.0 and below, the RSS Displayer block accepts a feed URL from any page editor and fetches it server-side without validation enabling redirect-to-internal bypasses. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.1 with a vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:N.