High severity · published Sep 15, 2026
CVE-2026-18423
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 allowing an authenticated user with permission on one Express entity to delete or rename saved search pres
7.1
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Concrete CMS · Concrete CMS
9.0.0 through 9.5.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18423
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18423
Broken Link
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes
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