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.
History

Thu, 21 May 2026 23:45:00 +0000

Type Values Removed Values Added
First Time appeared Concretecms
Concretecms concrete Cms
Vendors & Products Concretecms
Concretecms concrete Cms

Thu, 21 May 2026 22:15:00 +0000

Type Values Removed Values Added
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.
Title Concrete CMS 9.5.0 is vulnerable to SSRF via RSS Displayer Block
Weaknesses CWE-918
References
Metrics cvssV4_0

{'score': 2.1, '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: ConcreteCMS

Published:

Updated: 2026-05-21T21:43:44.845Z

Reserved: 2026-05-05T20:53:35.093Z

Link: CVE-2026-7890

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-21T22:16:49.400

Modified: 2026-05-21T22:16:49.400

Link: CVE-2026-7890

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-21T23:30:22Z