CVE-2026-3241

MEDIUM EPSS 11.0%
Published Mar 4, 20263mo ago · Modified Jun 17, 20262w ago
4.8 CVSS 4.0
Medium
Find Similar
Published Mar 4, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

Description

In Concrete CMS below version 9.4.8, a stored cross-site scripting (XSS) vulnerability exists in the "Legacy Form" block. An authenticated user with permissions to create or edit forms (e.g., a rogue administrator) can inject a persistent JavaScript payload into the options of a multiple-choice question (Checkbox List, Radio Buttons, or Select Box). This payload is then executed in the browser of any user who views the page containing the form. 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 M3dium for reporting.

CVSS Details

Base Score
4.8
Exploitability
—
Impact
—
Vector string
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/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 Low
Privileges Required High
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
11.0% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-79 Cross-site Scripting Injection

Affected Products 1

VendorProductVersionRange
concretecmsconcrete_cms* <9.4.8

References 2

  • documentation.concretecms.org https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notes
    PatchRelease NotesVendor Advisory
  • github.com https://github.com/concretecms/concretecms/pull/12826
    ExploitIssue TrackingVendor Advisory

Remediation

  • documentation.concretecms.org https://documentation.concretecms.org/9-x/developers/introduction/version-history/948-release-notes
    PatchRelease NotesVendor Advisory