Vulnerability · Published Sep 15, 2026 · Assigned by ConcreteCMS

CVE-2026-18423Concrete 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 allowing an authenticated user with permission on one Express entity to delete or rename saved search pres

Low 2.1

In plain English

A low-severity authorization bypass via user-controlled key in Concrete CMS from Concrete CMS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 4.0)2.1Low
Exploit odds (30 days)0.4%top 71.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

VendorProductVersions
Concrete CMS Concrete CMS 9.0.0 – through 9.5.2

Weakness: CWE-639 · 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

References