CRITICAL CVSS 9.8
Published: 2026-02-18

CVE-2026-27175

mjdm majordomo Security Advisory (CVE-2026-27175)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2026-27175?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2026-27175 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 OS command injection via rc/index.php. The $param variable from user input is interpolated into a command string within double quotes without sanitization via escapeshellarg(). The command is inserted into a database queue by safe_exec(), which performs no sanitization. The cycle_execs.php script, which is web-accessible without authentication, retrieves queued commands and passes them directly to exec(). An attacker can exploit a race condition by first triggering cycle_execs.php (which purges the queue and enters a polling loop), then injecting a malicious command via the rc endpoint while the worker is polling. The injected shell metacharacters expand inside double quotes, achieving remote code execution within one second.

📊 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-78

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-2026-27175 impacting mjdm majordomo.

⚡ Nuclei Detection Template (YAML) cve-2026-27175.yaml
id: cve-2026-27175

info:
  name: mjdm majordomo - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2026-27175 affecting mjdm majordomo.
    Evaluation: MajorDoMo (aka Major Domestic Module) is vulnerable to unauthenticated OS command injection via rc/index.php. The $param variable from user input is i...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2026-27175
  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-2026-27175
    cwe-id: CWE-78
  tags: cve,cve-2026-27175,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-2026-27175.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2026-27175
# 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-2026-27175 (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-2026-27175.sh
# Recommended Remediation & Patching Commands for CVE-2026-27175
# 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-2026-27175 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-2026-27175?

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-2026-27175?

CVE-2026-27175 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-2026-27175
Weakness CWE-78
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