Viruses and Worms, Protection from Disaster

Virus damage estimated at $55 billion in 2003.#1
"SINGAPORE - Trend Micro Inc, the world's* Linux: OS
third-largest anti-virus software maker, said Friday* Sendmail: mail server
that computer virus attacks cost global businesses an* Fetchmail: Grabs email from external email
estimated $55 billion in damages in 2003, a sum thataddresses
would rise this year. Companies lost roughly $20 billion* F-prot: Antivirus
to $30 billion in 2002 from the virus attacks, up from* SpamAssassin: Spam FilterSetup #2
about $13 billion in 2001, according to various industry* Win 2003 Server: OS
estimates." This was the story across thousands of* Exchange: Email server
news agencies desk January 2004. Out of $55 billion,* Symantec antivirus: Antivirus
how much did it cost your company? How much did* Exchange Intelligent Message Filter: Spam
it cost someone you know?I. The WhyFilterSoftware Updates
There is an average of 10-20 viruses released everyKeep you software up to date. Some worms and
day. Very few of these viruses actually make ?Wild?viruses replicate through vulnerabilities in services and
stage. Viruses are designed to take advantage ofsoftware on the target system. Code red is a classic
security flaws in software or operating systems.example. In august 2001, the worm used a known
These flaws can be as blatant as Microsoft Windowsbuffer overflow vulnerability in Microsoft's IIS 4.0 and
NetBIOS shares to exploits using buffer overflows.5.0 contained in the Idq.dll file. This would allow an
Buffer overflows happen when an attacker sendsattacker to run any program they wanted to on the
responses to a program longer then what isaffected system. Another famous worm called
expected. If the victim software is not designed well,Slammer targeted Microsoft SQL Server 2000 and
then the attacker can overwrite the memoryMicrosoft Desktop Engine (MSDE) 2000.When
allocated to the software and execute maliciousupdating your software, make sure to disable
code.People make viruses for various reasons. Thesefeatures and services that are not needed. Some
reasons range from political to financial to notorietyversions of WinNT had a web server called IIS
to hacking tools to plain malicious intent.Political:installed by default. If you do not need the service,
Mydoom is a good example of a virus that wasmake sure it is turned off (Code red is a perfect
spread with a political agenda. The two targets ofexample). By only enabling services you need, you
this virus were Microsoft and The SCO Group. Thedecrease the risk of attack.Telecommunications
SCO Group claims that they own a large portion ofSecurity
the Linux source code threatened to sue everyoneInstall a firewall on the network. A firewall is a
using Linux operating systems (with "stolen"device or software that blocks unwanted traffic
programming source). The virus was very effectivefrom going to or from the internal network. This
knocking down SCO's website. However, Microsoftgives you control of the traffic coming in and going
had enough time to prepare for the second attackout of your network. At minimum, block ports
and efficiently sidestepped disaster.Financial: Some135,137,139,445. This stops most network aware
virus writers are hired by other parties to either leachviruses and worms from spreading from the Internet.
financial data from a competitor or make theHowever, it is good practice to block all traffic unless
competitor look bad in the public eye. Industrialspecifically needed.Security Policies
espionage is a high risk/high payout field that can landImplementing security policies that cover items such
a person in prison for life.Notoriety: There are someas acceptable use, email retention, and remote
that write viruses for the sole purpose of gettingaccess can go a long way to protecting your
their name out. This is great when the virus writersinformation infrastructure. With the addition of annual
are script kiddies because this helps the authoritiestraining, employees will be informed enough to help
track them down. There are several famous viruseskeep the data reliable instead of hinder it. Every
that have the author's email in the source code orindividual that has access to your network or data
open scriptHacking Hackers sometimes writeneeds to follow these rules. It only takes one incident
controlled viruses to assist in the access of a remoteto compromise the system. Only install proven and
computer. They will add a payload to the virus suchscanned software on the system. The most
as a Trojan horse to allow easy access into thedamaging viruses come from installing or even
victims system.Malious: These are the people that areinserting a contaminated disk. Boot sector viruses can
the most dangerous. These are the blackhat hackersbe some of the hardest malware to defeat. Simply
that code viruses for the sole intention of destroyinginserting a floppy disk with a boot sector virus can
networks and systems without prejudice. They getimmediately transfer the virus to the hard drive.When
high on seeing the utter destruction of their creation,surfing the Internet, do not download untrusted files.
and are very rarely script kiddies.Many of the virusesMany websites will install Spyware, Adware, Parasites,
that are written and released are viruses altered byor Trojans in the name of "Marketing" on
script kiddies. These viruses are known asunsuspecting victims computers. Many prey on users
generations of the original virus and are very rarelythat do not read popup windows or download
altered enough to be noticeable from the original. Thisfreeware or shareware software. Some sites even
stems back to the fact that script kiddies do notuse code to take advantage of vulnerability in
understand what the original code does and onlyInternet explorer to automatically download and run
alters what they recognize (file extension or victim'sunauthorized software without giving you a choice.Do
website). This lack of knowledge makes script kiddiesnot install or use P2P programs like Kazaa, Morpheus,
very dangerous.II. The Howor Limewire. These programs install server software
Malicious code has been plaguing computer systemson your system; essentially back dooring your
since before computers became a commonsystem. There are also thousands of infected files
household appliance. Viruses and worms are examplesfloating on those networks that will activate when
of malicious code designed to spread and cause adownloaded.Backups & Disaster Recovery Planning
system to perform a function that it was notKeep daily backups offsite. These can be in the
originally designed to do.Viruses are programs thatform of tape, CD-R, DVD-R, removable hard drives,
need to be activated or run before they areor even secure file transfers. If data becomes
dangerous or spread. The computer system onlydamaged, you would be able to restore from the last
becomes infected once the program is run and theknown good backup. The most important step while
payload has bee deployed. This is why Hackers andfollowing a backup procedure is to verify that the
Crackers try to crash or restart a computer systembackup was a success. Too many people just
once they copy a virus onto it.There are four waysassume that the backup is working only to find out
a virus can spread:that the drive or media was bad six
1.) Emailmonths earlier when they were infected by a virus
2.) Networkor lost a hard drive. If the data that you are trying
3.) Downloading or installing softwarevto archive is less then five gig, DVD-R drives are a
4.) Inserting infected mediaSpreading through Emailgreat solution. Both the drives and disks have come
Many emails spread when a user receives andown in price and are now a viable option. This is also
infected email. When the user opens this email orone of the fastest backup methods to process and
previews it, the virus is now active and starts toverify. For larger backups, tape drives and removable
immediately spread.Spreading through Networkhard drives are the best option. If you choose this
Many viruses are network aware. This means thatmethod, you will need to rotate the backup with five
they look for unsecured systems on the networkor seven different media (tapes, CD/DVD, removable
and copy themselves to that system. This behaviordrives) to get the most out of the process. It is also
destroys network performance and causes virusessuggested to take a "master" backup out of the
to spread across your system like wildfire. Hackersrotation on a scheduled basis and archive offsite in a
and Crackers also use Internet and networkfireproof safe. This protects the data from fire,
connections to infect systems. They not only scanflood, and theft.In the Internet age, understanding
for unprotected systems, but they also targetthat you have to maintain these processes will help
systems that have known software vulnerabilities.you become successful when preventing damage and
This is why keeping systems up to date is sominimizes the time, costs, and liabilities involved during
important.Spreading through manual installationthe disaster recovery phase if you are
Installing software from downloads or disks increaseaffected.ResourcesVirus Resources
the risk of infection. Only install trusted and scannedF-PROT:
software that is known to be safe. Stay away fromMcAfee :
freeware and shareware products. These programsSymantec Norton:
are known to contain Spyware, Adware, and viruses.Trend Micro:
It is also good policy to deny all Internet softwareNIST GOV: software
that attempts to install itself unless explicitlyAVG Anti-Virus - Free
needed.Spreading through boot sectorsF-Prot - Free for home usersFree online Virus scan
Some viruses corrupt the boot sector of disks. ThisBitDefender -
means that if another disks scans the infected disk,HouseCall -
the infection spreads. Boot sector viruses areMcAffe -
automatically run immediately after the disk isPanda ActiveScan -
inserted or hard drive connected.III. Minimizing theRAV Antivirus - online Trojan scan
effect of viruses and wormsTrojanScan - online Security scan
We have all heard stories about the virus thatSymanted Security Check -
destroyed mission critical company data, which costTest my Firewall - Security Resources
companies months to recover and thousands ofForum of Incident Response and Security Teams:
dollars and man-hours restoring the information. In theMicrosoft:
end, there are still many hours, costs, and would beSANS Institute:
profits that remain unaccounted. Some companiesWebopedia:
never recover fully from a devastating attack. TakingDefinitionsAdware: *A form of spyware that collects
simple precautions can save your businessAnti-virusinformation about the user in order to display
Softwareadvertisements in the Web browser based on the
Another step is to run an antivirus program on theinformation it collects from the user's browsing
local computer. Many antivirus programs offer livepatterns.Software that is given to the user with
update software and automatically download theadvertisements already embedded in the
newest virus definitions minutes after they areapplicationMalware: *Short for malicious software,
released (Very important that you verify thesesoftware designed specifically to damage or disrupt a
updates weekly if not daily). Be careful of whichsystem, such as a virus or a Trojan horse.Script
antivirus program you chose. Installing a PC antivirusKiddie: *A person, normally someone who is not
on a network can be more destructive ontechnologically sophisticated, who randomly seeks out
performance than a virus at work. Norton makes ana specific weakness over the Internet in order to
effective corporate edition specifically designed forgain root access to a system without really
Windows NT Server and network environments.understanding what it is s/he is exploiting because
When using antivirus software on a network,the weakness was discovered by someone else. A
configure it to ignore network drives and partitions.script kiddie is not looking to target specific
Only scan the local system and turn off the autoinformation or a specific company but rather uses
protection feature. The auto-protect constantlyknowledge of a vulnerability to scan the entire
scans your network traffic and causes detrimentalInternet for a victim that possesses that
network issues. Corporate editions usually have thisvulnerability.Spyware: *Any software that covertly
disabled by default. PC editions do not.Email Clientsgathers user information through the user's Internet
Do not open emails from unknown sources. If youconnection without his or her knowledge, usually for
have a website for e-commerce transactions or toadvertising purposes. Spyware applications are
act as a virtual business card, make sure that thetypically bundled as a hidden component of freeware
emails come up with a preset subject. If the emailsor shareware programs that can be downloaded
are being sent through server side design instead offrom the Internet; however, it should be noted that
the users email client, specify whom it is coming fromthe majority of shareware and freeware applications
so you know what emails to trust. Use commondo not come with spyware. Once installed, the
sense when looking at your email. If you see aspyware monitors user activity on the Internet and
strange email with an attachment, do not open it untiltransmits that information in the background to
you verify whom it came from. This is how most MMsomeone else. Spyware can also gather information
worms spread.Disable preview panes in email clients.about e-mail addresses and even passwords and
Email clients such as Outlook and Outlook Expresscredit card numbers.Spyware is similar to a Trojan
have a feature that will allow you to preview thehorse in that users unwittingly install the product
message when the email is highlighted. This is a Majorwhen they install something else. A common way to
security flaw and will instantly unleash a virus if thebecome a victim of spyware is to download certain
email is infected.It is also a good idea to turn off thepeer-to-peer file swapping products that are available
feature that enables the client to view HTMLtoday.Aside from the questions of ethics and privacy,
formatted emails. Most of these viruses and wormsspyware steals from the user by using the
pass by using the html function "< i f r a m e s r c >"computer's memory resources and also by eating
and run the attached file within the email header.Webandwidth as it sends information back to the
will take a quick look at an email with the subjectspyware's home base via the user's Internet
header of "You're now infected" that will open a fileconnection. Because spyware is using memory and
called readme.exe."Subject: You're now infectedsystem resources, the applications running in the
MIME-Version: 1.0background can lead to system crashes or general
Content-Type: multipart/related;type="multipartsystem instability.Because spyware exists as
=="independent executable programs, they have the
X-Priority: 3ability to monitor keystrokes, scan files on the hard
X-MSMail-Priority: Normaldrive, snoop other applications, such as chat
X-Unsent: 1programs or word processors, install other spyware
To:programs, read cookies, change the default home
==page on the Web browser, consistently relaying this
Content-Type: multipartinformation back to the spyware author who will
==" *** (This calls theeither use it for advertising/marketing purposes or
iframe)--====_ABC0987654321DEF_====sell the information to another party.
Content-Type: text/html;charset="iso-8859-1"Licensing agreements that accompany software
Content-Transfer-Encoding: quoted-printable< H T Mdownloads sometimes warn the user that a spyware
L > < H E A D > < / H E A D > < B O D Y b g C o lprogram will be installed along with the requested
o r = 3 D # f f f f f f >software, but the licensing agreements may not
< i f r a m e s r c = 3 D c i d : EA4DMGBP9palways be read completely because the notice of a
height=3D0 width=3D0> *** (This calls readme.exe)spyware installation is often couched in obtuse,
< / i f r a m e > < / B O D Y > < / H T M Lhard-to-read legal disclaimers.Trojan: *A destructive
34567890DEF_====program that masquerades as a benign application.
Content-Type: audio/x-wav;name="readme.exe" ***Unlike viruses, Trojan horses do not replicate
(This is the virus/worm)themselves but they can be just as destructive. One
Content-Transfer-Encoding: base64of the most insidious types of Trojan horse is a
Content-ID: *** (Notice the < i f r a m e s r c = ?program that claims to rid your computer of viruses
L0RURCBIVE1MIDQuMCBUcmFuc2l0aW9ubut instead introduces viruses onto your
computer.The term comes from a story in Homer's
obydzIHRoZSBiZXN0LS0tLS0tPyAtIliad, in which the Greeks give a giant wooden horse
to their foes, the Trojans, ostensibly as a peace
JpcHQgbGFuZ3VhZ2U9amF2YXNjcmlwoffering. But after the Trojans drag the horse inside
their city walls, Greek soldiers sneak out of the
C5qcz9jdXN0b21lcmlkPTExNDc0horse's hollow belly and open the city gates, allowing
their compatriots to pour in and capture Troy.Virus:
U9ImphdmFzY3JpcHQiPg08IS0tDWZ1*A program or piece of code that is loaded onto
your computer without your knowledge and runs
2luTmFtZSxmZWF0dXJlcykgeyAvL3Yy*** Broken toagainst your wishes. Viruses can also replicate
protect the innocent. (Worm is encoded inthemselves. All computer viruses are man made. A
jb20vZmNhbGhpc3BvcnRzZnJtMT5Gb290simple virus that can make a copy of itself over and
over again is relatively easy to produce. Even such a
iAtIDwvZm9udD4NDTxicj48YnI+PGJysimple virus is dangerous because it will quickly use all
available memory and bring the system to a halt. An
5lemJvYXJkLmNvbS8+ZXpib2Fyeven more dangerous type of virus is one capable of
transmitting itself across networks and bypassing
k5LTIwMDEgZXpib2FyZCwgSW5jsecurity systems.Since 1987, when a virus infected
ARPANET, a large network used by the Defense
Cj==--====_ABC1234567890DEF_====--"EmailDepartment and many universities, many antivirus
Serversprograms have become available. These programs
The first step to minimizing the effect of viruses isperiodically check your computer system for the
to use an email server that filters incoming emailsbest-known types of viruses.Some people distinguish
using antivirus software. If the server is kept up tobetween general viruses and worms. A worm is a
date, it will catch the majority of Mass Mailer (MM)special type of virus that can replicate itself and use
worms. Ask your Internet Service Provider (ISP) ifmemory, but cannot attach itself to other
they offer antivirus protection and spam filtering onprograms.Worm: *A program or algorithm that
their email servers. This service is invaluable andreplicates itself over a computer network and usually
should always be included as the first line ofperforms malicious actions, such as using up the
defense.Many companies house an internal emailcomputer's resources and possibly shutting the
server that downloads all of the email from severalsystem down.* Definitions provided by WebopediaA
external email accounts and then runs an internal virusspecial thanks goes out to the CISSP community,
filter. Combining an internal email server with the ISPvarious Chief Information Security Officer (CISO)s,
protection is a perfect for a company with an ITand to those in the Risk assessment specialty of
staff. This option adds an extra layer of control, butInformation Systems Security for their help in proof
also adds more administration time.reading and suggestions.
Sample specs for an internal email server are:Setup