CVE-2025-8571: Concrete CMS vulnerable to Reflected Cross-Site Scripting (XSS) in Conversation Messages Dashboard Page

medium Affects concrete5/concrete5. Feed 2026.10.29.1, updated 2026-10-28; published 2025-08-06.

Concrete CMS vulnerable to Reflected Cross-Site Scripting (XSS) in Conversation Messages Dashboard Page

Package: concrete5/concrete5 Composer
Affected versions: <8.5.21 or >=9.0.0RC1 and <9.4.3
Fixed in: 8.5.21, 9.4.3
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (29.2th percentile)
Published: 2025-08-06
Source: osv.dev

References

NVD record concrete5/concrete5 advisories

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