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TCP
Vulnerable
445 SMB
SMB powers Windows file sharing, printer access, and some Active Directory-adjacent workflows.
Security Context
Port 445 is high-risk when broadly exposed. Treat it as an attack-surface decision, not just a connectivity setting, and confirm whether the listener truly needs to be reachable.
- !SMB exposure is associated with lateral movement and ransomware spread.
- !MS17-010 remains a well-known historical SMB risk marker.
Nmap Check
Use a version probe first so you confirm whether the expected service is really what is listening on this port.
nmap -sV -p 445 <host>Firewall Commands
UFW
sudo ufw allow 445/tcpiptables
sudo iptables -A INPUT -p tcp --dport 445 -j ACCEPT