Concrete CMS before 9.5.3 does not apply HTML entity encoding to user-defined Form block question labels when rendering them as column headers in the Dashboard Form Submissions report (concrete/single_pages/dashboard/reports/forms/legacy.php). a rogue editor could store markup or script in a label that then executes in the browser of any administrator who opens the submissions report for the affected form, producing stored cross-site scripting in the Dashboard. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 8.4 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.
{
"cna_assigner": "ConcreteCMS",
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81896.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"
]
}