CVE-2026-18119
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.
Scoring
- Severity
- HIGH
- CVSS base score
- 7
- CVSS 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
- EPSS probability
- 0.31%
- CWE
- CWE-79
- Published
- 2026-09-14
- Last modified
- 2026-09-14
Affected products
- Concrete CMS Concrete CMS
Weakness type
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