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Vulnerability record · CVE-2026-81896 · published 15 September 2026

CVE-2026-81896: Concretecms concrete cms cross-site scripting vulnerability

Concretecms · Concrete Cms

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.

8.4 CVSS 4.0 High EPSS 0.24% · top 86.7% CWE-79 · Cross-site scripting
8.4CVSS 4.0 base score
0.24%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
22 Sep 2026Last modified by NVD

Description

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.

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes Broken Link

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-81896), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.