MEDIUM CVSS 6.1
Published: 2020-12-17

CVE-2020-20138

cmsmadesimple cms_made_simple Security Advisory (CVE-2020-20138)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2020-20138 impacting cmsmadesimple cms_made_simple. Evaluated with CVSS Base Score of 6.1 (MEDIUM).

Original NVD Description

Source: NIST NVD
Cross Site Scripting (XSS) vulnerability in the Showtime2 Slideshow module in CMS Made Simple (CMSMS) 2.2.4.

📊 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
None (PR:N)
Unauthenticated execution
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 cmsmadesimple / cms_made_simple
Affected Versions 2.2.4
Weakness Enumeration CWE-79

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-2020-20138 impacting cmsmadesimple cms_made_simple.

⚡ Nuclei Detection Template (YAML) cve-2020-20138.yaml
id: cve-2020-20138

info:
  name: cmsmadesimple cms_made_simple - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: medium
  description: |
    Automated signature & scanner for CVE-2020-20138 affecting cmsmadesimple cms_made_simple.
    Evaluation: Cross Site Scripting (XSS) vulnerability in the Showtime2 Slideshow module in CMS Made Simple (CMSMS) 2.2.4....
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2020-20138
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2020-20138
    cwe-id: CWE-79
  tags: cve,cve-2020-20138,cmsmadesimple,cms_made_simple,medium

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "cms_made_simple"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2020-20138.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2020-20138
# Target: cmsmadesimple cms_made_simple | CVSS: 6.1 (MEDIUM)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2020-20138 (cmsmadesimple cms_made_simple)...")
    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 cmsmadesimple cms_made_simple scope (2.2.4).")
        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-2020-20138.sh
# Recommended Remediation & Patching Commands for CVE-2020-20138
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install cms_made_simple 2>/dev/null || \
sudo dnf upgrade cms_made_simple 2>/dev/null || \
sudo yum update cms_made_simple

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

# 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-2020-20138 in cmsmadesimple cms_made_simple?

Review vendor-specific security notices and update cmsmadesimple cms_made_simple 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-2020-20138?

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-2020-20138?

CVE-2020-20138 is classified with a CVSS 3.1 Base Score of 6.1 (MEDIUM). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
6.1
MEDIUM SEVERITY
CVE ID CVE-2020-20138
Weakness CWE-79
Vendor cmsmadesimple
Product cms_made_simple
Published 2020-12-17
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N