How can I configure firewall rules for minimal attack surface?

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    # Example firewall configuration using iptables
    # Default policy to drop all incoming and forwarding traffic
    iptables -P INPUT DROP
    iptables -P FORWARD DROP
    iptables -P OUTPUT ACCEPT

    # Allow incoming traffic on port 80 (HTTP) and 443 (HTTPS)
    iptables -A INPUT -p tcp --dport 80 -j ACCEPT
    iptables -A INPUT -p tcp --dport 443 -j ACCEPT

    # Allow traffic from established connections
    iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT

    # Allow loopback interface traffic
    iptables -A INPUT -i lo -j ACCEPT
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