A computer forensics investigator analyzing firewall logs observes unusual traffic patterns. What can be inferred?

• A. A smurf attack has been attempted
• B. A denial of service has been attempted
• C. Network intrusion has occurred
• D. Buffer overflow attempt on the firewall

Answer: (C)

Unusual traffic patterns in firewall logs point to someone or something probing or attempting to access the network, which is the sign of a network intrusion. Firewalls monitor traffic and raise alerts when activity falls outside normal baselines, so anomalies typically indicate unauthorized access attempts, scans, or exploitation efforts. The other options describe specific attack types: a smurf attack is a particular DoS method using spoofed ICMP requests, a generic denial of service would show as a sustained flood of traffic to services, and a buffer overflow attempt on the firewall would usually appear as exploit-specific payloads or signatures. With only the observation of unusual traffic, the most general and supported inference is that a network intrusion is occurring or underway.