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.

CVSS

No CVSS.

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 20:16

Updated : 2026-09-15 14:40

NVD link : CVE-2026-18119

Mitre link : CVE-2026-18119

CVE.ORG link : CVE-2026-18119

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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