nerdexam
CompTIA

CS0-003 · Question #551

A security analyst observes a high volume of SYN flags from an unexpected source toward a web application server within one hour. The traffic is not flagging for any exploit signatures. Which of the f

The correct answer is C. An attacker is executing reconnaissance activities by mapping which ports are open and closed.. A high volume of SYN flags without completing the three-way TCP handshake (SYN-ACK and ACK) is characteristic of reconnaissance activities, such as a TCP SYN scan. Attackers use SYN scans to map open and closed ports on a target system without fully establishing connections. The

Submitted by lucia.co· Mar 6, 2026Security operations

Question

A security analyst observes a high volume of SYN flags from an unexpected source toward a web application server within one hour. The traffic is not flagging for any exploit signatures. Which of the following scenarios best describes this activity?

Options

  • AA legitimate connection is continuously attempting to establish a connection with a downed web
  • BA script kiddie is attempting to execute a DDoS through a ping flood attack.
  • CAn attacker is executing reconnaissance activities by mapping which ports are open and closed.
  • DA web exploit attempt is likely occurring and the security analyst is not seeing it.

How the community answered

(24 responses)
  • A
    8% (2)
  • B
    4% (1)
  • C
    83% (20)
  • D
    4% (1)

Explanation

A high volume of SYN flags without completing the three-way TCP handshake (SYN-ACK and ACK) is characteristic of reconnaissance activities, such as a TCP SYN scan. Attackers use SYN scans to map open and closed ports on a target system without fully establishing connections. The lack of exploit signatures in the traffic supports the conclusion that this is reconnaissance rather than an active exploitation attempt.

Topics

#Network traffic analysis#SYN flood#Reconnaissance#Port scanning

Community Discussion

No community discussion yet for this question.

Full CS0-003 Practice