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GPEN · Question #406

Identify the network activity shown below;

The correct answer is D. An attempt to impersonate the local gateway. The activity shows ARP spoofing, where crafted ARP replies falsely map the attacker's MAC address to the gateway's IP to intercept LAN traffic.

Exploitation & Post-Exploitation Techniques

Question

Identify the network activity shown below;

Exhibit

GPEN question #406 exhibit

Options

  • AA sweep of available hosts on the local subnet
  • BA flood of the local switch's CAM table.
  • CAn attempt to disassociate wireless clients.
  • DAn attempt to impersonate the local gateway

How the community answered

(25 responses)
  • A
    8% (2)
  • B
    4% (1)
  • C
    4% (1)
  • D
    84% (21)

Why each option

The activity shows ARP spoofing, where crafted ARP replies falsely map the attacker's MAC address to the gateway's IP to intercept LAN traffic.

AA sweep of available hosts on the local subnet

A host sweep generates ARP requests or ICMP probes sent sequentially across subnet IP addresses to discover live hosts, producing a request-based pattern rather than forged ARP replies claiming an existing host's identity.

BA flood of the local switch's CAM table.

CAM table flooding requires sending frames with large numbers of unique spoofed source MAC addresses to overflow the switch's forwarding table and force broadcast behavior, which is structurally different from ARP reply manipulation targeting a single IP.

CAn attempt to disassociate wireless clients.

Wireless client disassociation sends forged IEEE 802.11 deauthentication frames to disconnect clients from an access point and is specific to wireless networks, not Ethernet-layer ARP traffic.

DAn attempt to impersonate the local gatewayCorrect

In an ARP spoofing attack, the attacker sends unsolicited ARP reply packets that associate their MAC address with the IP address of the default gateway, causing LAN hosts to forward outbound traffic to the attacker instead of the legitimate router. This positions the attacker as a man-in-the-middle capable of intercepting, inspecting, or modifying traffic. The telltale pattern is repeated gratuitous ARP replies from a MAC address that does not match the legitimate gateway's recorded binding.

Concept tested: ARP spoofing to impersonate the default gateway

Source: https://attack.mitre.org/techniques/T1557/002/

Topics

#ARP spoofing#gateway impersonation#MITM attack#network traffic analysis

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