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CVE PROGRAM SOURCE RECORD7.0 High

CVE-2026-18119

Concrete CMS below 9.5.3 is vulnerable to Stored XSS via unsanitized inline block custom style values

Description

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Concrete CMS Concrete CMS

Default version status: unaffected

  • 5.0.0 to ≤ 9.5.2affected

References