Low severity · published Sep 15, 2026
CVE-2026-68533
Missing Authorization in Concrete CMS versions below 9.5.3 Conversation File Upload Allows File Import Without the Add Message Attachments Permission
2.3
CVSS
0.4%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CC
Concrete CMS · Concrete CMS
5.0.0 through 9.5.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-68533
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-68533
documentation.concretecms.org
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes
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