The Daserf backdoor was used to move laterally within the network from compromised host 192.168.1.15 to target host 192.168.1.25. The attacker established a connection from external IP 203.0.113.45, executing the malicious payload identified by hash d41d8cd98f00b204e9800998ecf8427e. The attacker aims to expand their network foothold by accessing additional systems.