What Is A Ping Of Death Attack; What Is A Teardrop Attack; What Is A Syn Flood Attack; What Is A Land Attack - ZyXEL Communications P-2608HWL-D1 Support Notes

2. Those that exploits weaknesses in the TCP/IP specification such as SYN Flood and LAND
Attacks.
3. Brute-force attacks that flood a network with useless data such as Smurf attack.
4. IP Spoofing

What is a Ping of Death attack?

Ping of Death attacks use a 'PING' utility to create an IP packet that exceeds the maximum 65535 bytes of
data allowed by the IP specification. The oversized packet is then sent to an unsuspecting system which
may crash, hang, or reboot.

What is a Teardrop attack?

Teardrop attacks exploit weakness during the reassembling of IP packet fragments. As data is transmitted
through a network, IP packets are often broken up into smaller chunks. Each fragment looks like the
original packet except that it contains an offset field. The Teardrop program creates a series of IP
fragments with overlapping offset fields. When these fragments are reassembled at the destination, some
systems will crash, hang, or reboot.

What is a SYN Flood attack?

SYN attacks flood a targeted system with a series of SYN packets. Each packet causes the targeted
system to issue a SYN-ACK response. While the targeted system waits for the ACK that follows a
SYN-ACK, it queues up all outstanding SYN-ACK responses on what is known as a backlog queue.
SYN-ACKs are moved off the queue only when an ACK comes back or when an internal timer (which is
set a relatively long intervals) terminates the TCP three-way handshake. Once the queue is full , the
system will ignore all incoming SYN requests, making the system unavailable for legitimate users.

What is a LAND attack?

In a LAN attack, hackers flood SYN packets to the network with a spoofed source IP address of the
targeted system. This makes it appear as if the host computer sent the packets to itself, making the system
unavailable while the target system tries to respond to itself.

What is a Brute-force attack?

A Brute-force attack, such as 'Smurf' attack, targets a feature in the IP specification known as directed or
subnet broadcasting, to quickly flood the target network with useless data. A Smurf hacker flood a
destination IP address of each packet using the broadcast address of the network. Thus the router will
All contents copyright (c) 2005 ZyXEL Communications Corporation.
P-2608HWL Series Support Notes
165