CVE-2026-8203
HIGH EPSS 2.3%
Published May 21, 20261mo ago · Modified Jun 17, 20261w ago
7.3 CVSS 4.0
Published May 21, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago
Description
Concrete CMS 9.5.0 and below has Stored XSS on the height parameter. The controller does not validate or sanitize $height. Any user with editor privileges can inject malicious JavaScript that executes in the context of any visitor's browser, potentially leading to session hijacking, credential theft, or other malicious actions. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Alfin Joseph for reporting.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity High
Privileges Required High
User Interaction P
Scope X
Threat Intelligence
EPSS Exploit Probability
2.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-79 Cross-site Scripting Injection
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| concretecms | concrete_cms | * | ≤9.5.0 |
References 1
- documentation.concretecms.org https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.