The basics of Virus and Anti-virus...

1. Virus And Antivirus
presented by
Arkaprabha Pal
Roll-09, ECE, 3rd
year
1
24/03/2015 Virus & Antivirus
Kalyani Govt. Engg. College
Dept. of ECE

2. Content
1. What is Computer Virus?
2. Discovery of Computer Virus
3. Types of computer Virus
4. Characteristics
5. How does virus work?
6. Symptoms of an infection
7. Protection measures
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3. Content–contd.
8. What is Anti-Virus?
9. Types of Anti-Virus
10. How does it work?
11. How to detect?
12. How to remove?
13. Conclusion
14. Reference
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4. 1. What is Computer Virus?
Virus: A self-replicating piece of computer code
that can partially or fully attach itself to files or
applications, and can cause your computer to do
something you don't want it to do.
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5. 2.Discovery of comp. virus
• Creeper virus
• First detected on ARPANET, in early 1970s
• Propagated from TENEX operating system
• The first pc virus
• a boot sector virus- “brain”.It was created by Basit and Amjad
Farooq Alvi, in 1986, Lahore, Pakistan.
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6. 3. Types of computer Virus
Virus
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Boot Sector
Virus
File Infector
Virus
Multi-
partite
Virus
Macro Virus Trojan Worm
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7. 4.Characteristics
• Memory Resident
• Non-Resident
• Stealth
• Encrypting
• Polymorphic
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8. 5. How does virus work?
• The Basic Rule
• A virus code has mainly two parts first one is replication
routine & another one payload routine. Using these two
procedures virus mainly spread.
• Boot Infectors
• If the boot code on the drive is infected, the boot virus can
travel to every disk that is read and the infection spreads.
• Program Infectors
• When an infected application is run, the virus activates and
any program file subsequently run becomes infected.
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9. 6. Symptoms of an infection
• File deletion
• Phantom Message
• Makes Slower
• Pop-Ups
• Erratic (and unwanted) behavior
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10. 7. Protection measures
• Get a latest Anti-Virus Software.
• Make sure to have a latest security patches and
hot fixes using windows update.
• Use a Host-Based Firewall.
• Backup important files.
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11. 8. What is Anti-Virus?
• Computer programs intended to detect, prevents
and takes action to disarm or remove malicious
software programs, i.e. viruses and worms.
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12. 9. Types of Anti-Virus
• Depending on the installation method of the
Anti-Virus these can be in the following forms:
–On-Access scanners
–On-Demand scanners
–Hardware Anti-Virus products
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13. 10. How does it work?
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Source System
Interception
Disinfection
Alert
Dest. System
yes
No
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14. 11. How to detect?
• Scan the computer memory and disks.
• Use memory-resident anti-virus software to
monitor continuously the computer for viruses.
• You should make sure that an up-to-date virus
definition data have been applied.
• Use server-based anti-virus software to protect
your network.
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15. 12. How to remove?
• Stop all activities on infected machine and
perform the actions given by Anti-Virus.
• Repair the file if possible.
• If repair is not possible, move the file to Anti-Virus
Quarantine.
• If the above actions failed then Delete the File.
• And if all the previous actions failed, then format your disk or
restore from your backup.
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16. 13. Conclusion
• Be careful when use software and files.
• Be alert for virus activities.
• Be calm when virus attacks.
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17. 14. Reference
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Web sites:
• www.wikipedia.org
• www.microsoft.com
• www.symantec.com
• www.mcafee.com
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18. The End
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