ZyXEL Communications ZyWALL 300 Manuale Utente
Chapter 29 IDP
ZyWALL USG 300 User’s Guide
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29.8.3 IDP Service Groups
An IDP service group is a set of related packet inspection signatures.
DoS/DDoS
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.
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.
Scan
A scan describes the action of searching a network for an exposed service.
An attack may then occur once a vulnerability has been found. Scans occur
on several network levels.
A network scan occurs at layer-3. For example, an attacker looks for network
devices such as a router or server running in an IP network.
A scan on a protocol is commonly referred to as a layer-4 scan. For example,
once an attacker has found a live end system, he looks for open ports.
A scan on a service is commonly referred to a layer-7 scan. For example,
once an attacker has found an open port, say port 80 on a server, he
determines that it is a HTTP service run by some web server application. He
then uses a web vulnerability scanner (for example, Nikto) to look for
documented vulnerabilities.
An attack may then occur once a vulnerability has been found. Scans occur
on several network levels.
A network scan occurs at layer-3. For example, an attacker looks for network
devices such as a router or server running in an IP network.
A scan on a protocol is commonly referred to as a layer-4 scan. For example,
once an attacker has found a live end system, he looks for open ports.
A scan on a service is commonly referred to a layer-7 scan. For example,
once an attacker has found an open port, say port 80 on a server, he
determines that it is a HTTP service run by some web server application. He
then uses a web vulnerability scanner (for example, Nikto) to look for
documented vulnerabilities.
Buffer Overflow
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.
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.
Virus/Worm
A computer virus is a small program designed to corrupt and/or alter the
operation of other legitimate programs. A worm is a program that is designed
to copy itself from one computer to another on a network. A worm’s
uncontrolled replication consumes system resources, thus slowing or
stopping other tasks.
operation of other legitimate programs. A worm is a program that is designed
to copy itself from one computer to another on a network. A worm’s
uncontrolled replication consumes system resources, thus slowing or
stopping other tasks.
Backdoor/Trojan
A backdoor (also called a trapdoor) is hidden software or a hardware
mechanism that can be triggered to gain access to a program, online service
or an entire computer system. A Trojan horse is a harmful program that is
hidden inside apparently harmless programs or data.
Although a virus, a worm and a Trojan are different types of attacks, they can
be blended into one attack. For example, W32/Blaster and W32/Sasser are
blended attacks that feature a combination of a worm and a Trojan.
mechanism that can be triggered to gain access to a program, online service
or an entire computer system. A Trojan horse is a harmful program that is
hidden inside apparently harmless programs or data.
Although a virus, a worm and a Trojan are different types of attacks, they can
be blended into one attack. For example, W32/Blaster and W32/Sasser are
blended attacks that feature a combination of a worm and a Trojan.
Access Control
Access control refers to procedures and controls that limit or detect access.
Access control attacks try to bypass validation checks in order to access
network resources such as servers, directories, and files.
Access control attacks try to bypass validation checks in order to access
network resources such as servers, directories, and files.
Web Attack
Web attacks refer to attacks on web servers such as IIS (Internet Information
Services).
Services).
Table 132 Policy Types (continued)
POLICY TYPE
DESCRIPTION
Table 133 IDP Service Groups
WEB_PHP WEB_MISC WEB_IIS WEB_FRONTPAGE
WEB_CGI WEB_ATTACKS
TFTP
TELNET
SQL SNMP
SMTP RSERVICES
RPC POP3
POP2
P2P
ORACLE
NNTP NETBIOS MYSQL