CVE-2026-68533

Low

Description

Concrete CMS below 9.5.3 conversation attachment uploaded endpoint imported files into the file manager before evaluating the "Add Message Attachments" permission, which was only checked after the file had been stored. A user denied that permission, or an unauthenticated visitor on a guest-posting configuration, could import approved files of allowed types into the file manager. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N. Thanks riodrwn for reporting.

SeverityLow
CVSS2.3
Exploit probability—
ProductConcrete CMS
PublishedSep 15, 2026
First seenSep 15, 2026

How to fix

Affected products

ProductAffected versionsFixed in
Concrete CMS Concrete CMS5.0.0 ≤ v ≤ 9.5.2—

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