User manual

Viruses and more
Avira Server Security - User Manual (Status: 16 Dec. 2013) 29
Script viruses and worms use one of the script languages, such as Javascript, VBScript
etc., to insert themselves in other, new scripts or to spread themselves by calling operating
system functions. This frequently happens via email or through the exchange of files
(documents).
A worm is a program that multiplies itself but that does not infect the host. Worms cannot
consequently form part of other program sequences. Worms are often the only possibility
to infiltrate any kind of damaging programs on systems with restrictive security measures.
Spyware
Spyware are so called spy programs that intercept or take partial control of a computer's
operation without the user's informed consent. Spyware is designed to exploit infected
computers for commercial gain.
Trojan horses (short Trojans)
Trojans are pretty common nowadays. Trojans include programs that pretend to have a
particular function, but that show their real image after execution and carry out a different
function that, in most cases, is destructive. Trojan horses cannot multiply themselves,
which differentiates them from viruses and worms. Most of them have an interesting name
(SEX.EXE or STARTME.EXE) with the intention to induce the user to start the Trojan.
Immediately after execution they become active and can, for example, format the hard
disk. A dropper is a special form of Trojan that 'drops' viruses, i.e. embeds viruses on the
computer system.
Zombie
A zombie PC is a computer that is infected with malware programs and that enables
hackers to abuse computers via remote control for criminal purposes. On command, the
affected PC starts denial-of-service (DoS) attacks, for example, or sends spam and
phishing emails.
7.2 Threat categories
Adware
Adware is software that presents banner ads or in pop-up windows through a bar that
appears on a computer screen. These advertisements usually cannot be removed and are
consequently always visible. The connection data allow many conclusions on the usage
behavior and are problematic in terms of data security.
Your Avira product detects Adware. If the Adware option is enabled with a check mark in
the configuration under Threat categories, you receive a corresponding alert if your Avira
product detects adware.