CVE-2026-7890

MEDIUM

Concrete CMS 9.5.0 is vulnerable to SSRF via RSS Displayer Block

Title source: cna
STIX 2.1

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.

References (1)

Core 1

Scores

CVSS v3 6.4
EPSS 0.0015
EPSS Percentile 4.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-918
Status published
Products (2)
Concrete CMS/Concrete CMS 5.0 - 9.5.0
concretecms/concrete_cms < 9.5.1
Published May 21, 2026
Tracked Since May 22, 2026