CVE-2026-3242 PUBLISHED

Concrete CMS below 9.4.8 is vulnerable to Stored XSS in the Switch Language block

Assigner: ConcreteCMS
Reserved: 26.02.2026 Published: 04.03.2026 Updated: 04.03.2026

In Concrete CMS below version 9.4.8, a rogue administrator can add stored XSS via the Switch Language block. 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.

Metrics

CVSS 4.0

CVSS 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
CVSS Score: 4.8

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	Low	Integrity	None
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	High
User Interaction	Passive

CVSS 4.0

Product Status

Vendor	Concrete CMS
Product	Concrete CMS
Versions	Default: unaffected affected from 5 to 9.4.8 (excl.)

Credits

M3dium reporter

References

Problem Types

CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') CWE

Impacts

CAPEC-592 Stored XSS