ip tables commands which ‘might’ make your firewall PCI compliant

This is a list of the iptables commands that will setup a minimal firewall which ‘might’ be PCI compliant

This is primarily here to remind me, so I have a reference in the future.

I also have ports for FTP and SSH for a single developer IP as well as monitoring for a single monitoring server.   The format is simple and can easily be changed for other services.

Be sure to replace ‘my.ip’ with your development ip,  and ‘monitoring.ip’ with

This is on a Linux Ubuntu machine (of course)

apt-get install iptables iptables-persistent

iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -s my.ip/32 -j ACCEPT
iptables -A INPUT -p tcp --dport 21 -s my.ip/32 -j ACCEPT
iptables -A INPUT -p tcp --dport 5666 -s monitoring.ip/32-j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -p udp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -p udp --dport 443 -j ACCEPT
iptables -A INPUT -j REJECT --reject-with icmp-host-unreachable


iptables -A INPUT -p icmp --icmp-type timestamp-request -j DROP
iptables -A OUTPUT -p icmp --icmp-type timestamp-reply -j DROP

iptables -t raw -A PREROUTING -p tcp --tcp-flags FIN,SYN FIN,SYN -j DROP
iptables -t raw -A PREROUTING -p tcp --tcp-flags SYN,RST SYN,RST -j DROP
iptables -t raw -A PREROUTING -p tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH,URG -j DROP
iptables -t raw -A PREROUTING -p tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN -j DROP
iptables -t raw -A PREROUTING -p tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
iptables -t raw -A PREROUTING -p tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN,RST,PSH,ACK,URG -j DROP
iptables-save > /etc/iptables/rules.v4