CVE-2026-3240
MEDIUMConcrete CMS < 9.4.8 - Stored Cross-Site Scripting via Legacy Form Question Field
Title source: llmDescription
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.
References (2)
Core 2
Core References
Various Sources
https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notes
Issue Tracking
https://github.com/concretecms/concretecms/pull/12826
Scores
CVSS v3
4.8
EPSS
0.0021
EPSS Percentile
11.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-79
Status
published
Products (2)
concrete5/concrete5
0 - 9.4.8Packagist
concretecms/concrete_cms
< 9.4.8
Published
Mar 04, 2026
Tracked Since
Mar 04, 2026