CVE-2026-18423

High

Description

Concrete CMS 9.0.0 through 9.5.2 is vulnerable to Insecure direct object reference (IDOR) in the Express saved search preset delete and edit dialogs . An authenticated user holding only view permission on a single Express entity could therefore permanently delete, with no undo, or rename saved search presets owned by Express entities for which they had no permission, and a renamed preset name was displayed back to users of the targeted entity, enabling defacement or social engineering. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N. Thanks Yalguun Tumenkhuu ( fg0x0 ) for reporting.

SeverityHigh
CVSS7.1
Exploit probability—
ProductConcretecms Concrete Cms
PublishedSep 15, 2026
First seenSep 15, 2026

How to fix

Update
  • concretecms concrete_cms9.5.3 or later

Affected products

ProductAffected versionsFixed in
concretecms concrete_cms9.0.0 ≤ v < 9.5.39.5.3

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