Auditing Information Security Management - Auditing Information Systems: Enhancing Performance of the Enterprise - page 101

Worms spread from one computer to the other unaided using the com-
puter transport system. The worm has the capability to replicate itself and
infect many files on computers and external storage devices.

1 Worms

Malware ( mal icious soft ware ) steal information on infected computers
such as login and credit card information. Malware includes such variants
as spyware and adware.

2 Malware

Key loggers record (or log) keystrokes on a keyboard connected to an in-
fected computer without the users knowing in order to steal passwords or
credit card information.

Key Log-
gers

3

A Trojan appears to be a legitimate file or software but behaves in a dif-
ferent way when installed or copied on a computer, such as deleting,
blocking, or corrupting files.

4 Trojans

A computer virus attaches itself to a program file or document allowing it
to spread as the files are copied across computers.

5 Viruses

A time bomb virus executes a malicious function at a specified time and
date. The malicious function may include deleting files or corrupting
files.

Time
Bomb

6

Denial of
Service
(DOS) at-
tack

The DOS attack is carried out on an infected computer or network by
flooding it with several requests which blocks the computer from operat-
ing normally.

7

A backdoor virus enters a computer without being detected and opens
ports which are used by third parties to control or steal information.

8 Backdoor

Email spam is the sending of identical mail messages to different recipi-
ents from infected computers or user email accounts. Spam email can also
contain links which can lead to phishing websites hosting malware.

9 Spam

10 Adware Adware pops up unwanted advertisements on infected computers.

Figure 7.3 Types of Viruses
In order to properly manage and control virus infections, an enterprise needs to invest in a
good and robust antivirus software. There are many antivirus solutions on the market ran-
ging from single-user software to large enterprise solutions which can be used to manage
thousands of users. An enterprise needs to investigate antivirus solutions on the market and
select an appropriate solution.