CAS-002 · Question #216
The Information Security Officer (ISO) believes that the company has been targeted by cybercriminals and it is under a cyber attack. Internal services that are normally available to the public via…
The correct answer is A. After the senior engineer used a network analyzer to identify an active Fraggle attack, the. The log entries show multiple external source IPs sending UDP traffic on port 19 to the company's external router IP. Port 19 is the chargen (character generator) service. A Fraggle attack is a UDP-based amplification/reflection DDoS attack that exploits chargen (port 19) or…
Question
The Information Security Officer (ISO) believes that the company has been targeted by cybercriminals and it is under a cyber attack. Internal services that are normally available to the public via the Internet are inaccessible, and employees in the office are unable to browse the Internet. The senior security engineer starts by reviewing the bandwidth at the border router, and notices that the incoming bandwidth on the router's external interface is maxed out. The security engineer then inspects the following piece of log to try and determine the reason for the downtime, focusing on the company's external router's IP which is 128.20.176.19:
11:16:22.110343 IP 90.237.31.27.19 > 128.20.176.19.19: UDP, length 1400 11:16:22.110351 IP 23.27.112.200.19 > 128.20.176.19.19: UDP, length 1400 11:16:22.110358 IP 192.200.132.213.19 > 128.20.176.19.19: UDP, length 1400 11:16:22.110402 IP 70.192.2.55.19 > 128.20.176.19.19: UDP, length 1400 11:16:22.110406 IP 112.201.7.39.19 > 128.20.176.19.19: UDP, length 1400 Which of the following describes the findings the senior security engineer should report to the ISO and the BEST solution for service restoration?
Options
- AAfter the senior engineer used a network analyzer to identify an active Fraggle attack, the
- BAfter the senior engineer used the above IPS logs to detect the ongoing DDOS attack, an
- CAfter the senior engineer used a mirror port to capture the ongoing amplification attack, a
- DAfter the senior engineer used a packet capture to identify an active Smurf attack, an ACL
How the community answered
(37 responses)- A68% (25)
- B5% (2)
- C19% (7)
- D8% (3)
Explanation
The log entries show multiple external source IPs sending UDP traffic on port 19 to the company's external router IP. Port 19 is the chargen (character generator) service. A Fraggle attack is a UDP-based amplification/reflection DDoS attack that exploits chargen (port 19) or echo (port 7) services to flood a target. Multiple external IPs sending UDP/19 traffic directly to the target is the signature of a Fraggle attack. A Smurf attack (option D) uses ICMP echo requests sent to broadcast addresses-not UDP. Since the traffic is incoming (amplified responses), a network analyzer-not IPS logs (B) or a mirror port (C)-is the tool used to identify the attack pattern. The recommended remediation is an ACL to block the malicious UDP traffic at the border router.
Topics
Community Discussion
No community discussion yet for this question.