CVE-2026-3240 (GCVE-0-2026-3240)
Vulnerability from cvelistv5 – Published: 2026-03-04 02:15 – Updated: 2026-03-04 15:33
VLAI
EPSS
VEX
Title
Concrete CMS below 9.4.8 is vulnerable to Stored XSS via Legacy form
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-04 15:32 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')
Assigner
ConcreteCMS
CNA
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Concrete CMS | Concrete CMS |
Affected:
5 , < 9.4.8
(git)
|
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Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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