Helping Hand Questions for CEH-001

Sniffing is considered a passive attack.

In a typical MAC flooding attack, a switch is flooded with packets, each containing different source MAC addresses. The intention is to consume the limited memory set aside in the switch to store the MAC address-to-physical port translation table.The result of this attack causes the switch to enter a state called failopen mode, in which all incoming packets are broadcast out on all ports (as with a hub), instead of just down the correct port as per normal operation. The principle of ARP spoofing is to send fake, or 'spoofed', ARP messages to an Ethernet LAN. These frames contain false MAC addresses, confusing network devices, such as network switches. As a result frames intended for one machine can be mistakenly sent to another (allowing the packets to be sniffed) or an unreachable host (a denial of service attack).

Securing DNS servers should be a priority of the organization. Hackers obtaining DNS information can discover a wealth of information about an organization. This information can be used to further exploit the network.

This log entry shows a hacker using a buffer overflow to fill the data buffer and trying to insert the execution of /bin/sh into the executable code part of the thread. It is probably an existing exploit that is used, or a directed attack with a custom built buffer overflow with the “payload” that launches the command shell.