CRITICAL CVSS 9.8
Published: 2026-02-18

CVE-2026-27180

mjdm majordomo Security Advisory (CVE-2026-27180)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-27180 impacting mjdm majordomo. Evaluated with CVSS Base Score of 9.8 (CRITICAL).

Original NVD Description

Source: NIST NVD
MajorDoMo (aka Major Domestic Module) is vulnerable to unauthenticated remote code execution through supply chain compromise via update URL poisoning. The saverestore module exposes its admin() method through the /objects/?module=saverestore endpoint without authentication because it uses gr('mode') (which reads directly from $_REQUEST) instead of the framework's $this->mode. An attacker can poison the system update URL via the auto_update_settings mode handler, then trigger the force_update handler to initiate the update chain. The autoUpdateSystem() method fetches an Atom feed from the attacker-controlled URL with trivial validation, downloads a tarball via curl with TLS verification disabled (CURLOPT_SSL_VERIFYPEER set to FALSE), extracts it using exec('tar xzvf ...'), and copies all extracted files to the document root using copyTree(). This allows an attacker to deploy arbitrary PHP files, including webshells, to the webroot with two GET requests.

📊 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
None (UI:N)
Zero human interaction required
Scope
Unchanged (S:U)
Confined to same security context
Confidentiality
High (C:H)
Total information disclosure
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product mjdm / majordomo
Affected Versions -
Weakness Enumeration CWE-494

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-2026-27180 impacting mjdm majordomo.

⚡ Nuclei Detection Template (YAML) cve-2026-27180.yaml
id: cve-2026-27180

info:
  name: mjdm majordomo - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2026-27180 affecting mjdm majordomo.
    Evaluation: MajorDoMo (aka Major Domestic Module) is vulnerable to unauthenticated remote code execution through supply chain compromise via update URL poisoning....
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-27180
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2026-27180
    cwe-id: CWE-494
  tags: cve,cve-2026-27180,mjdm,majordomo,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "majordomo"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2026-27180.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-27180
# Target: mjdm majordomo | CVSS: 9.8 (CRITICAL)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2026-27180 (mjdm majordomo)...")
    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 mjdm majordomo 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-2026-27180.sh
# Recommended Remediation & Patching Commands for CVE-2026-27180
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install majordomo 2>/dev/null || \
sudo dnf upgrade majordomo 2>/dev/null || \
sudo yum update majordomo

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

# 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.

🔗 Verified Technical References

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2026-27180 in mjdm majordomo?

Review vendor-specific security notices and update mjdm majordomo 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-2026-27180?

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-2026-27180?

CVE-2026-27180 is classified with a CVSS 3.1 Base Score of 9.8 (CRITICAL). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
9.8
CRITICAL SEVERITY
CVE ID CVE-2026-27180
Weakness CWE-494
Vendor mjdm
Product majordomo
Published 2026-02-18
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H