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.
Published: 2026-09-14
Score: 7 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Fri, 18 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 9.0, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H'}


Mon, 14 Sep 2026 23:45:00 +0000

Type Values Removed Values Added
First Time appeared Concretecms
Concretecms concrete Cms
Vendors & Products Concretecms
Concretecms concrete Cms

Mon, 14 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 14 Sep 2026 21:00:00 +0000

Type Values Removed Values Added
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.
Title Concrete CMS below 9.5.3 is vulnerable to Stored XSS via unsanitized inline block custom style values
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 7, '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'}


Subscriptions

Concretecms Concrete Cms
cve-icon MITRE

Status: PUBLISHED

Assigner: ConcreteCMS

Published:

Updated: 2026-09-14T20:07:08.323Z

Reserved: 2026-07-28T18:02:02.837Z

Link: CVE-2026-18119

cve-icon Vulnrichment

Updated: 2026-09-14T20:07:00.322Z

cve-icon NVD

Status : Analyzed

Published: 2026-09-14T20:16:42.563

Modified: 2026-09-18T19:23:08.313

Link: CVE-2026-18119

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-15T12:00:16Z

Weaknesses
  • CWE-79

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