In what type of attack does an attacker capture packets containing passwords or digital signatures whenever packets pass between two hosts on a network?

A dictionary attack attempts to crack passwords offline by systematically trying words from a predefined list, not by capturing live network packets.

A ping flood attack overwhelms a target with ICMP echo requests to cause a denial of service, not to capture authentication credentials.

A DoS attack aims to disrupt availability of a service rather than capture and reuse authentication data from network traffic.

In a replay attack, the attacker eavesdrops on network traffic to capture packets containing credentials or digital signatures, then retransmits those packets to impersonate the original sender. The attacker does not need to decrypt the captured data - simply resending valid authentication material is sufficient to authenticate as the victim. This attack specifically targets the integrity and freshness of authentication exchanges.