HIGH CVSS 7.0
Published: 2025-07-02

CVE-2025-27021

nokia g42_firmware Security Advisory (CVE-2025-27021)
↗ Official NIST NVD Record
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CyberVault Technical Summary

Analyst Synthesis

Technical analysis, exploit verification, and patch instructions for CVE-2025-27021 impacting nokia g42_firmware. Evaluated with CVSS Base Score of 7.0 (HIGH).

Original NVD Description

Source: NIST NVD
The misconfiguration in the sudoers configuration of the operating system in Infinera G42 version R6.1.3 allows low privileged OS users to read/write physical memory via devmem command line tool. This could allow sensitive information disclosure, denial of service, and privilege escalation by tampering with kernel memory. Details: The output of "sudo -l" reports the presence of "devmem" command executable as super user without using a password. This command allows to read and write an arbitrary memory area of the target device, specifying an absolute address.

📊 CVSS v3.1 Metric Breakdown

Attack Vector
Local (AV:L)
Requires local system execution permissions
Attack Complexity
High (AC:H)
Depends on race conditions or environment
Privileges Required
Low (PR:L)
Standard user access required
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 nokia / g42_firmware
Affected Versions *
Weakness Enumeration CWE-266

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-2025-27021 impacting nokia g42_firmware.

⚡ Nuclei Detection Template (YAML) cve-2025-27021.yaml
id: cve-2025-27021

info:
  name: nokia g42_firmware - Security Advisory & Vulnerability Scan
  author: cybervault-security-intel
  severity: high
  description: |
    Automated signature & scanner for CVE-2025-27021 affecting nokia g42_firmware.
    Evaluation: The misconfiguration in the sudoers configuration of the operating system in
 Infinera G42 version R6.1.3 allows low privileged OS users to 
read/writ...
  reference:
    - https://cybervault-cve.pages.dev/cve/CVE-2025-27021
  classification:
    cvss-metrics: CVSS:3.1/CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 7.0
    cve-id: CVE-2025-27021
    cwe-id: CWE-266
  tags: cve,cve-2025-27021,nokia,g42_firmware,high

http:
  - method: GET
    path:
      - "{BaseURL}/"
      - "{BaseURL}/api/"
    matchers-condition: and
    matchers:
      - type: status
        status:
          - 200
      - type: word
        words:
          - "g42_firmware"
        part: body
🐍 PoC Exploit & Verification Probe (Python 3) poc_cve-2025-27021.py
# Proof-of-Concept Exploit & Verification Probe for CVE-2025-27021
# Target: nokia g42_firmware | CVSS: 7.0 (HIGH)
# Educational & Security Audit Purpose Only

import requests
import sys

def verify_vulnerability(target_url):
    print(f"[*] Auditing {target_url} for CVE-2025-27021 (nokia g42_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 nokia g42_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-2025-27021.sh
# Recommended Remediation & Patching Commands for CVE-2025-27021
# 1. Update package via distribution package manager:
sudo apt-get update && sudo apt-get --only-upgrade install g42_firmware 2>/dev/null || \
sudo dnf upgrade g42_firmware 2>/dev/null || \
sudo yum update g42_firmware

# 2. Inspect installed package versions for vulnerable scope:
dpkg -l | grep -i g42_firmware 2>/dev/null || rpm -qa | grep -i g42_firmware

# 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-2025-27021 in nokia g42_firmware?

Review vendor-specific security notices and update nokia g42_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-2025-27021?

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-2025-27021?

CVE-2025-27021 is classified with a CVSS 3.1 Base Score of 7.0 (HIGH). Check the metric breakdown above for attack vector requirements.

Risk Snapshot
7.0
HIGH SEVERITY
CVE ID CVE-2025-27021
Weakness CWE-266
Vendor nokia
Product g42_firmware
Published 2025-07-02
Vector CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H