Figure 113 Attack Types; Table 77 Attack Types - ZyXEL Communications Internet Security Appliance ZyWALL5UTM 4.0 User Manual

ZyWALL 5/35/70 Series User's Guide
To see signatures listed by intrusion type supported by the ZyWALL, select that type from the
Attack Type list box.

Figure 113 Attack Types

The following table describes each attack type.

Table 77 Attack Types

TYPE
DoS/DDoS
Buffer Overflow
Access Control
Scan
Trojan Horse
P2P
IM
243
DESCRIPTION
The goal of Denial of Service (DoS) attacks is not to steal information, but to
disable a device or network on the Internet. A distributed denial-of-service (DDoS)
attack is one in which multiple compromised systems attack a single target,
thereby causing denial of service for users of the targeted system.
A buffer overflow occurs when a program or process tries to store more data in a
buffer (temporary data storage area) than it was intended to hold. The excess
information can overflow into adjacent buffers, corrupting or overwriting the valid
data held in them.
Intruders could run codes in the overflow buffer region to obtain control of the
system, install a backdoor or use the victim to launch attacks on other devices.
Access control refers to procedures and controls that limit or detect access. Access
control is used typically to control user access to network resources such as
servers, directories, and files.
Scan refers to all port, IP or vulnerability scans. Hackers scan ports to find targets.
They may use a TCP connect() call, SYN scanning (half-open scanning), Nmap
etc. After a target has been found, a vulnerability scanner can be used to exploit
exposures.
A Trojan horse is a harmful program that's hidden inside apparently harmless
programs or data. It could be used to steal information or remotely control a device.
Peer-to-peer (P2P) is where computing devices link directly to each other and can
directly initiate communication with each other; they do not need an intermediary. A
device can be both the client and the server. In the ZyWALL, P2P refers to peer-to-
peer applications such as eMule, eDonkey, BitTorrent, iMesh etc.
IM (Instant Messaging) refers to chat applications. Chat is real-time communication
between two or more users via networks-connected computers. After you enter a
chat (or chat room), any member can type a message that will appear on the
monitors of all the other participants.
Chapter 13 Configuring IDP