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TI-2025-07849 Aliases CVE-2025-8571GHSA-4pcg-pjp5-3mc6

Improper input validation in Concrete CMS

Priority LOW 22CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00383 32nd percentileScored 2026-11-07
Fix Fixed Concrete CMS (Concrete CMS): 9.4.3, 8.5.21concrete5/concrete5 (Packagist): 8.5.21, 9.4.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Concrete CMSConcrete CMS9.0.0 to before 9.4.3; 5.6 to before 8.5.219.4.3, 8.5.21Patch availableCNA
—concrete5/concrete5 (Packagist)before 8.5.218.5.21Patch availableGHSA-4pcg-pjp5-3mc6
—concrete5/concrete5 (Packagist)9.0.0RC1 to before 9.4.39.4.3Patch availableGHSA-4pcg-pjp5-3mc6
  • Concrete CMS VendorConcrete CMS Affected 9.0.0 to before 9.4.3; 5.6 to before 8.5.21 Fixed in 9.4.3, 8.5.21 Patch available CNA
  • concrete5/concrete5 (Packagist) Vendor— Affected before 8.5.21 Fixed in 8.5.21 Patch available GHSA-4pcg-pjp5-3mc6
  • concrete5/concrete5 (Packagist) Vendor— Affected 9.0.0RC1 to before 9.4.3 Fixed in 9.4.3 Patch available GHSA-4pcg-pjp5-3mc6

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*before 8.5.21; 9.0 to before 9.4.3VulnerableConcrete CMS
  • cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:* Versions before 8.5.21; 9.0 to before 9.4.3 Vulnerable ·Concrete CMS

Remediation

  • Fix · CNA Concrete CMS (Concrete CMS) Fixed in 9.4.3, 8.5.21
  • Fix · GHSA-4pcg-pjp5-3mc6 concrete5/concrete5 (Packagist) Fixed in 8.5.21 Advisory →
  • Fix · GHSA-4pcg-pjp5-3mc6 concrete5/concrete5 (Packagist) Fixed in 9.4.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-8571
  2. 2026-10-03 Alias added: GHSA-4pcg-pjp5-3mc6

References

Advisory 1

Other 6

  • TI-2026-23602 ConcreteCMS v9.4.7 contains a Denial of Service (DoS) vulnerability in the File Manager… CVSS 3.1MEDIUM 6.5
  • TI-2023-23992 A Cross Site Scripting (XSS) vulnerability in Concrete CMS from versions 9.2.0 to 9.2.2… CVSS 3.1MEDIUM 5.4
  • TI-2023-26495 Concrete CMS before 8.5.13 and 9.x before 9.2.2 allows unauthorized access because… CVSS 3.1CRITICAL 9.8
  • TI-2026-14907 Missing authorization in Concrete CMS CVSS 4.0HIGH 8.7
  • TI-2022-06200 Cleartext transmission of sensitive information in https://github.com/concrete5/concrete5 CVSS 3.1CRITICAL 9.8
  • TI-2021-17294 An issue was discovered in Concrete CMS through 8.5.5. CVSS 3.1CRITICAL 9.8
See all 197 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences