CRITICAL CVSS 9.8
Published: 2021-04-22

CVE-2021-25669

siemens scalance_x200-4p_irt_firmware Security Advisory (CVE-2021-25669)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2021-25669 impacting siemens scalance_x200-4p_irt_firmware. Evaluated with CVSS Base Score of 9.8 (CRITICAL).

Original NVD Description

Source: NIST NVD
A vulnerability has been identified in SCALANCE X200-4P IRT (All versions < 5.5.1), SCALANCE X201-3P IRT (All versions < 5.5.1), SCALANCE X201-3P IRT PRO (All versions < 5.5.1), SCALANCE X202-2 IRT (All versions < 5.5.1), SCALANCE X202-2P IRT (incl. SIPLUS NET variant) (All versions < 5.5.1), SCALANCE X202-2P IRT PRO (All versions < 5.5.1), SCALANCE X204 IRT (All versions < 5.5.1), SCALANCE X204 IRT PRO (All versions < 5.5.1), SCALANCE X204-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X204-2FM (All versions < V5.2.5), SCALANCE X204-2LD (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X204-2LD TS (All versions < V5.2.5), SCALANCE X204-2TS (All versions < V5.2.5), SCALANCE X206-1 (All versions < V5.2.5), SCALANCE X206-1LD (All versions < V5.2.5), SCALANCE X208 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X208PRO (All versions < V5.2.5), SCALANCE X212-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE X212-2LD (All versions < V5.2.5), SCALANCE X216 (All versions < V5.2.5), SCALANCE X224 (All versions < V5.2.5), SCALANCE XF201-3P IRT (All versions < 5.5.1), SCALANCE XF202-2P IRT (All versions < 5.5.1), SCALANCE XF204 (All versions < V5.2.5), SCALANCE XF204 IRT (All versions < 5.5.1), SCALANCE XF204-2 (incl. SIPLUS NET variant) (All versions < V5.2.5), SCALANCE XF204-2BA IRT (All versions < 5.5.1), SCALANCE XF206-1 (All versions < V5.2.5), SCALANCE XF208 (All versions < V5.2.5). Incorrect processing of POST requests in the web server may write out of bounds in stack. An attacker might leverage this to denial-of-service of the device or remote code execution.

📊 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 siemens / scalance_x200-4p_irt_firmware
Affected Versions *
Weakness Enumeration CWE-121

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-2021-25669 impacting siemens scalance_x200-4p_irt_firmware.

⚡ Nuclei Detection Template (YAML) cve-2021-25669.yaml
id: cve-2021-25669

info:
  name: siemens scalance_x200-4p_irt_firmware - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: critical
  description: |
    Automated signature & scanner for CVE-2021-25669 affecting siemens scalance_x200-4p_irt_firmware.
    Evaluation: A vulnerability has been identified in SCALANCE X200-4P IRT (All versions &lt; 5.5.1), SCALANCE X201-3P IRT (All versions &lt; 5.5.1), SCALANCE X201-3...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2021-25669
  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-2021-25669
    cwe-id: CWE-121
  tags: cve,cve-2021-25669,siemens,scalance_x200-4p_irt_firm,critical

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "scalance_x200-4p_irt_firmware"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2021-25669.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2021-25669
# Target: siemens scalance_x200-4p_irt_firmware | 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-2021-25669 (siemens scalance_x200-4p_irt_firmware)...")
    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 siemens scalance_x200-4p_irt_firmware 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-2021-25669.sh
# Recommended Remediation & Patching Commands for CVE-2021-25669
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install scalance_x200-4p_irt_firm 2>/dev/null || \
sudo dnf upgrade scalance_x200-4p_irt_firm 2>/dev/null || \
sudo yum update scalance_x200-4p_irt_firm

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i scalance_x200-4p_irt_firm 2>/dev/null || rpm -qa | grep -i scalance_x200-4p_irt_firm

# 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

Authorities
  • No records filed in this category.
Distributions
  • No records filed in this category.

❓ Frequently Asked Questions (FAQ) & Remediation Guide

How do I fix CVE-2021-25669 in siemens scalance_x200-4p_irt_firmware?

Review vendor-specific security notices and update siemens scalance_x200-4p_irt_firmware 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-2021-25669?

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-2021-25669?

CVE-2021-25669 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-2021-25669
Weakness CWE-121
Vendor siemens
Product scalance_x200-4p_irt_firmware
Published 2021-04-22
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H