Concrete CMS before 9.5.3 is vulnerable to Cross-Site Request Forgery (CSRF) in the theme page-template activation feature. The Dashboard theme Inspect controller's activate_files() action created PageTemplate records from attacker-supplied pageTemplates[] values without validating an anti-CSRF token.A remote attacker could host a page that auto-submitted a forged POST request; when a signed-in administrator visited it, the request executed under the administrator's session and created theme page-template records, changing site configuration without the administrator's consent. 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:N/SC:N/SI:N/SA:N. Thanks Andrew Gonzalez for reporting.
{
"cna_assigner": "ConcreteCMS",
"cwe_ids": [
"CWE-352"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81924.json"
}{
"cpe": "cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "5.0.0"
},
{
"last_affected": "9.5.2"
},
{
"introduced": "0"
},
{
"fixed": "9.5.3"
}
],
"source": [
"AFFECTED_FIELD",
"CPE_RANGE"
]
}