By: Angelica Jurczak

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Computer Viruses

• By Angelica Jurczak
• Anna Rog
• David Brackett

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What is a Computer Virus?

• A computer virus is a computer program that can
  copy itself and infect a computer without the
  permission or knowledge of the owner.
• One of the first detected virus was the Creeper
  virus in the early 70s
• Before computer networks became widespread, most
  viruses spread on removable media, particularly
  floppy disk.

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Basic Computer Viruses

• Trojan Horses
• appears as interesting program file but when
  installed it allows intruders to access and read
  your files
• Worms
• virus that copies and multiplies itself by
  using computer networks and security
  flaws
• E-mail Viruses
• use e-mail messages to spread which allow it to
  automatically forward itself to thousands of
  people

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Types of Viruses

• Boot Sector Virus
• Infects the boot or MBR of diskettes and hard
  drives through the sharing of infected disks and
  pirated software applications
• Once your hard drive is infected all diskettes
  that you use in your computer will be infected
• Program Virus
• Becomes active when the program file (usually
  with extensions .BIN, .COM, .EXE, .OVL, .DRV)
  carrying the virus is opened
• It then makes copies of itself and will infect
  other programs on the computer
• Multipartite Virus
• Hybrid of a Boot Sector and Program viruses
• It infects program files and when the infected
  program is active it will affect the boot record

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Types of Viruses

• Stealth Virus
• Disguises itself to prevent from being detected
  by antivirus software
• It alters its file size or conceals itself in
  memory
• Polymorphic Virus
• Act like a chameleon, changing its virus
  signature (binary pattern) every time it
  multiples and infects a new file
• Macro Virus
• Programmed as a macro embedded in a document,
  usually found in Microsoft Word and Excel
• Once it gets in to your computer, every document
  you produce will become infected
• Relatively new type of virus and may slip by your
  antivirus software if you don't have the most
  recent version installed

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Signs Your Computer is Infected

• Functions slower than normal
• Responds slowly and freezes often
• Restarts itself often
• See uncommon error messages, distorted menus, and
  dialog boxes
• Notice applications fail to work correctly
• Fail to print correctly

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Computer Virus History
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• First half of the 70'Late 60,s, early 70,s-
  "Rabbits" cloned themselves occupied system
  resources, slowing down the productivity. 
• -"The Creeper"  capable of entering a network by
  itself and transferring a copy of itself to the
  system.
• Early 80,s-Increasing number of programs written
  by individuals not by software companies.
  Programs caused miner viruses called "Trojan
  horses".
• 1986'Brain virus' - by Amjad and Basit Farooq
  Alvi.
• spread through floppy disks,
  
• infected boot records and not computer hard
  drives
• Lahore, Pakistani Brain, Brain-A and UIUC virus
• -took over free space on the floppy disk and
  hid from detection
  
  disguised itself by displaying the uninfected
  boot sector on the disk.
• 1987-Lehigh virus
• - the first memory resident file infector that
  attacked executable files and took control when a
  file was opened
• The Jerusalem Virus
• -had bugs that re-infected programs that were
  already infected

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• 1988 Robert Morris made a worm that invaded
  ARPANET computers
• disabled 6,000 computers on the network by
  overflowing their memory banks with copies of
  itself
• 1991 Norton Anti-Virus software
• 1999 "Melissa" virus
• -infected thousands of computers very fast by
  sending copies of itself to 50 names in the
  address book on Outlook e-mail
• Led to an estimated 80 million in damage and
  record sales of anti-virus products.
• 2000 "I Love You" virus
• -was sent by email and infected 10 of computers
  in only one day
• -created by a young Filipino computer student who
  did not get punished because then the Philippines
  had no laws against hacking which led to the
  European Union's global Cybercrime Treaty.
• 2001 "Nimda" virus (days after 9/11)
• -had 5 ways of infecting systems

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• 2004
• MyDoom spreads through emails and file-sharing
  software faster than any previous virus or worm.
• Allows hackers to access the hard drive of the
  infected computer.
• An estimated one million computers running
  Windows are affected by the fast-spreading Sasser
  computer worm.
• The worm does not cause irreparable harm to
  computers or data, but it does slow computers and
  cause some to quit or reboot without explanation.
• 2006
• Discovery of the first-ever malware trojan horse
  for Mac OS X
• 2008
• Torpig is a Trojan horse which affects Windows,
  turning off anti-virus applications.
• It allows others to access the computer, modifies
  data, steals confidential information and
  installs malware on the victim's computer.
• 2009
• Conficker infects anywhere from 9 to 15 million
  Microsoft server systems.
• French air force, Royal Navy warships and
  submarines, Sheffield Hospital network, UK
  Ministry of Defence, German Bundeswehr and
  Norwegian Police were all affected.

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• Total Number of Viruses by year January 1985 1
  January 1985 1 January 1987 3 January 1989 6
  January 1990 142 January 1991 357 January 1992
  1,161 January 1993 2,482 January 1994 3,687
  January 1995 5,626 January 1996 7,764 January
  1997 11,037 January 1998 16,726 January 1999
  40,850 January 2000 44,000 January 2001 48,000
  January 2002 55,000 January 2003 62,000

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Melissa

• Another virus that fired up the media was
  Melissa, a Word macro virus.
• When people received the host Word document via
  email and opened it, the virus sent a copy of
  itself to the first 50 people in the victim's
  address book.
• Named after a topless dancer in Florida, the
  Melissa virus crashed the email servers of
  corporations and governments in different spots
  around the world.
• The Computer Emergency Response Team, set up
  after Robert Morris mucked up the Internet with
  his worm in 1988, estimated that the virus hit
  100,000 computers in its first weekend.
• David L. Smith posted the infected file to an
  alt.sex usenet group using a stolen AOL account.
  Initially he entered a plea of innocence, but
  after being confronted with a maximum sentence of
  40 years in prison, he eventually pled guilty and
  received a much-reduced sentence.

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Love You, Love Bug

• By almost any measure, the so-called Love Bug was
  the most damaging and costly virus ever. I don't
  know who comes up with these whack figures, but
  according to Reuters the bug cost the world 15
  billion in lost productivity.
• The Love Bug spread far faster than Melissa.
  Unlike Melissa, it would mail itself to everyone
  in your Outlook address book -- most of whom
  would probably be delighted to read about how you
  love them -- not just the first fifty. Moreover,
  it would gobble up certain media files stored on
  your hard drive.

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Did you know?

• One German newspaper tragically lost 2,000
  pictures from its archive.
• The perpetrator turned out to be a 23-year-old
  Filipino computer science student who more or
  less plagiarized all of his code.
• The lack of laws in the Philippines covering
  computer crimes, he pretty much got away with his
  crime.

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Prevention

• Upload and use antivirus software
• Be aware of the e-mails and attachments you open
• Check for updates on antivirus software regularly
• Make sure antivirus software is installed
  correctly

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Sources
http//www.tech-faq.com/history-of-computer-viruse
s.shtml http//spamlaws.com/history.html http//
en.wikipedia.org/wiki/Computer_virusHistory http
//www.infoplease.com/ipa/A0872842.html
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References

• http//www.spamlaws.com/protect.htmlhttp//www.sp
  amlaws.com/virus-types.htmlhttp//www.spamlaws.co
  m/virus-comtypes.html
• http//www.spamlaws.com/federal/index.shtml
• http//www.spamlaws.com/virus-types.html
• Wikipedia
• www.suggestafix.com
• www.microsoft.com