6e - Viruses

6e - Viruses

1. Viruses

   • A program which infects computer systems by self-replicating
   • Infection by a virus can:
     • Cause harm to data on a computer
     • Collect information about a user without the user's knowledge (spyware)
   • Computers can be infected by viruses when new data is introduced to the computer:
     • Removable media - USB, memory cards
     • Across a network - LAN, via Internet

2. Boot Sector Viruses

   • Spreads by hiding itself in the boot sector of the hard drive or floppy disk
   • Any new disk, CD or memory stick inserted in the computer will become infected
     • If this storage medium is used on another computer, it becomes infected

3. Email Virus

   • Contained in attachments to email messages
   • Replicates itself by automatically mailing itself to people in the vivtim's email address book
   • Spreads very rapidly

4. Trojan

   • A computer programme
   • A programme claims to do one thing, but instead does damage when its run
     • Deletes files
     • Erase hard disk
   • Opens computer up to malicious intruders, allowing them to read your files

5. Macro Virus

   • Infects word processor files, spreadsheets, databases etc.
   • Can spread very quickly if files is used by many people
   • Microsoft added protection, so now recieve a warning