CVE-2026-3240
mediumpriority · track · 19EPSS 0.002 · 13 %ileEUUSEPSS · scored 2026-10-26
In Concrete CMS below version 9.4.8, a user with permission to edit a page with element Legacy form can perform a stored XSS attack towards high-privilege accounts via the Question field. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 4.8 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N Thanks minhnn42, namdi and quanlna2 from VCSLab-Viettel Cyber Security for reporting.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.1–4.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-45fj-fvmm-xcc5Concrete CMS has a stored Cross-site Scripting (XSS) vulnerability2026-03-04ghsa · osvUS
In Concrete CMS below version 9.4.8, a user with permission to edit a page with element Legacy form can perform a stored XSS attack towards high-privilege accounts via the Question field. The Concrete CMS security team thanks minhnn42, namdi and quanlna2 from VCSLab-Viettel Cyber Security for reporting.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notescnnvd
- https://github.com/concretecms/concretecms/pull/12826cnnvd
- https://www.concretecms.org/downloadPatchcnnvd
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notesenisa_euvd
- https://github.com/concretecms/concretecms/pull/12826enisa_euvd
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notesPatchRelease NotesVendor Advisorynvd
- https://github.com/concretecms/concretecms/pull/12826ExploitIssue TrackingVendor Advisorynvd
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