What does the Check Point Firewall do with packets that are explicitly rejected by the rule definition?

When a Check Point Firewall encounters packets that are explicitly rejected by a rule definition, it will drop them silently. This means that the firewall does not send back any notification or message to the sender about the dropped packets. This behavior is designed to maintain security by preventing the sender from learning about the firewall's configuration or the existence of specific rules that deny traffic. By not responding to rejected packets with an error message or a log (unless explicitly configured to do so), the firewall helps to obscure the network’s architecture and potential vulnerabilities from malicious actors.

In contrast, alternative actions such as logging the dropped packets or sending error messages would indicate to the sender that something has occurred, potentially giving insights into the network's defenses that could be exploited. Therefore, the chosen action of silently dropping explicitly rejected packets is consistent with good security practices.