CVE-2025-8571 MEDIUM

CVE-2025-8571: Concrete CMS 9 through 9.4.2 and below 8.5.21 is vulnerable to Reflected Cross-Site Scripting (XSS) in Conversation Messages Dashboard Page

Vendor Concrete Cms
Product Concrete CMS
Weakness CWE-20 · Input validation
Published August 5, 2025
Last update August 6, 2025
View on NVD All CVEs

CVSS base score

4.8/10
Attack vector Network
Attack complexity Low
Privileges required High
User interaction —
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Concrete CMS 9 to 9.4.2 and versions below 8.5.21 are vulnerable to Reflected Cross-Site Scripting (XSS) in the Conversation Messages Dashboard Page. Unsanitized input could cause theft of session cookies or tokens, defacement of web content, redirection to malicious sites, and (if victim is an admin), the execution of unauthorized actions. 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:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Fortbridge https://fortbridge.co.uk/  for performing a penetration test and vulnerability assessment on Concrete CMS and reporting this issue.

Key dates

02Disclosure timeline

August 5, 2025 CVE published
August 6, 2025 Record updated