CRITICAL CVSS 9.1
Published: 2021-02-12

CVE-2021-20651

elecom file_manager Security Advisory (CVE-2021-20651)
↗ Official NIST NVD Record
Seeking technical exploit breakdowns or verified PoC code for CVE-2021-20651?
🔬 Search Writeups & Exploit Archive →

CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2021-20651 impacting elecom file_manager. Evaluated with CVSS Base Score of 9.1 (CRITICAL).

Original NVD Description

Source: NIST NVD
Directory traversal vulnerability in ELECOM File Manager all versions allows remote attackers to create an arbitrary file or overwrite an existing file in a directory which can be accessed with the application privileges via unspecified vectors.

📊 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
None (C:N)
No data confidentiality impact
Integrity
High (I:H)
Total modification of target system
Availability
High (A:H)
Total denial of service or shutdown

🎯 Affected Versions Matrix

Affected Product elecom / file_manager
Affected Versions *
Weakness Enumeration CWE-22

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-2021-20651 impacting elecom file_manager.

⚡ Nuclei Detection Template (YAML) cve-2021-20651.yaml
id: cve-2021-20651

info:
  name: elecom file_manager - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2021-20651 affecting elecom file_manager.
    Evaluation: Directory traversal vulnerability in ELECOM File Manager all versions allows remote attackers to create an arbitrary file or overwrite an existing fil...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2021-20651
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
    cvss-score: 9.1
    cve-id: CVE-2021-20651
    cwe-id: CWE-22
  tags: cve,cve-2021-20651,elecom,file_manager,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "file_manager"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2021-20651.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2021-20651
# Target: elecom file_manager | CVSS: 9.1 (CRITICAL)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2021-20651 (elecom file_manager)...")
    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 elecom file_manager 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-2021-20651.sh
# Recommended Remediation & Patching Commands for CVE-2021-20651
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install file_manager 2>/dev/null || \
sudo dnf upgrade file_manager 2>/dev/null || \
sudo yum update file_manager

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

# 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-2021-20651 in elecom file_manager?

Review vendor-specific security notices and update elecom file_manager 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-2021-20651?

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-2021-20651?

CVE-2021-20651 is classified with a CVSS 3.1 Base Score of 9.1 (CRITICAL). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
9.1
CRITICAL SEVERITY
CVE ID CVE-2021-20651
Weakness CWE-22
Vendor elecom
Product file_manager
Published 2021-02-12
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H