MEDIUM CVSS 4.8
Published: 2025-08-05

CVE-2025-8571

concretecms concrete_cms Security Advisory (CVE-2025-8571)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2025-8571 impacting concretecms concrete_cms. Evaluated with CVSS Base Score of 4.8 (MEDIUM).

Original NVD Description

Source: NIST NVD
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.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Network (AV:N)
Exploitable remotely across internet boundaries
Attack Complexity
Low (AC:L)
No specialized conditions required
Privileges Required
High (PR:H)
Administrative credentials required
User Interaction
Required (UI:R)
User must click or open resource
Scope
Changed (S:C)
Impacts components beyond caller authority
Confidentiality
Low (C:L)
Partial information leakage
Integrity
Low (I:L)
Partial data modification possible
Availability
None (A:N)
No system availability impact

🎯 Affected Versions Matrix

Affected Product concretecms / concrete_cms
Affected Versions *
Weakness Enumeration CWE-20

Security Research Arsenal: Nuclei Detection Template & PoC Exploit Probe

High-Intent Research Tool

Ready-to-use security scanner signatures, active verification probe skeletons, and remediation playbooks for CVE-2025-8571 impacting concretecms concrete_cms.

⚡ Nuclei Detection Template (YAML) cve-2025-8571.yaml
id: cve-2025-8571

info:
  name: concretecms concrete_cms - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2025-8571 affecting concretecms concrete_cms.
    Evaluation: 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. ...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2025-8571
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 4.8
    cve-id: CVE-2025-8571
    cwe-id: CWE-20
  tags: cve,cve-2025-8571,concretecms,concrete_cms,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "concrete_cms"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2025-8571.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2025-8571
# Target: concretecms concrete_cms | CVSS: 4.8 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2025-8571 (concretecms concrete_cms)...")
    headers = {
        "User-Agent": "CyberVault-Audit-Scanner/2.0",
        "Accept": "*/*"
    }
    try:
        r = requests.get(f"{target_url.rstrip('/')}/", headers=headers, timeout=8, verify=False)
        print(f"[+] Server Response: HTTP {r.status_code} | Server Banner: {r.headers.get('Server', 'Unknown')}")
        if r.status_code < 500:
            print(f"[!] Target reachable. Verify version against concretecms concrete_cms scope (*).")
        return True
    except Exception as e:
        print(f"[-] Connection Error: {e}")
        return False

if __name__ == '__main__':
    url = sys.argv[1] if len(sys.argv) > 1 else "http://localhost:8080"
    verify_vulnerability(url)
🛡️ Quick Patch & Remediation Script (Bash) patch_cve-2025-8571.sh
# Recommended Remediation & Patching Commands for CVE-2025-8571
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install concrete_cms 2>/dev/null || \
sudo dnf upgrade concrete_cms 2>/dev/null || \
sudo yum update concrete_cms

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i concrete_cms 2>/dev/null || rpm -qa | grep -i concrete_cms

# 3. Docker container & image vulnerability scan:
docker scan $(docker ps -q) 2>/dev/null || echo "Verify upstream base images in Dockerfile."

🛡️ Remediation & Security Action

  • Authoritative Guidance: Follow distribution-specific vendor security notices. Advisory status and package patches vary by distribution release.
  • Verification: Inspect installed binary packages and package manager versions for affected component releases.
  • Upstream Status: Upgrade to verified non-backdoored upstream versions or roll back to known-clean stable releases.
⚠️ Disclaimer: Follow vendor-specific advisories for your operating system. CyberVault does not fabricate unsupported remediation scripts.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2025-8571 in concretecms concrete_cms?

Review vendor-specific security notices and update concretecms concrete_cms packages to the latest patched release immediately. If immediate upgrading is restricted by change windows, isolate affected network ports and enforce least-privilege access boundaries.

Is there an active exploit or public PoC for CVE-2025-8571?

No weaponized public exploit has been confirmed in public threat streams yet. Continuous surveillance is active across GitHub and security feeds.

What is the CVSS 3.1 severity rating and impact for CVE-2025-8571?

CVE-2025-8571 is classified with a CVSS 3.1 Base Score of 4.8 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
4.8
MEDIUM SEVERITY
CVE ID CVE-2025-8571
Weakness CWE-20
Vendor concretecms
Product concrete_cms
Published 2025-08-05
Vector CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N