CVE-2026-18119
Concrete CMS below 9.5.3 is vulnerable to Stored XSS via unsanitized inline block custom style values
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
Concrete CMS below 9.5.3 did not sanitize custom style values in the Block Design dialog before writing them into page CSS via a DOM sink, permitting stored cross-site scripting. An editor-level user could execute script in an administrator's session and escalate privileges. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 7.0 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Nguyen Manh Thuan for reporting.
| CWE | CWE-79 |
| Vendor | concrete cms |
| Product | concrete cms |
| Published | Sep 14, 2026 |
| Last Updated | Sep 14, 2026 |
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Affected Versions
Concrete CMS / Concrete CMS
5.0.0 ≤ 9.5.2
References
Credits
manhthuan