viruses and its types in the computer system
- 1. VIRUS
- 2. A computer virus is a type of malicious software that, when executed, replicates itself by modifying other computer programs and inserting its own code. When this replication succeeds, the affected areas are then said to be "infected" with a computer virus.
- 3. CONTENTS Similarities Between Biological & Computer Virus How Does A Virus Work? Life Cycle Of Computer Virus. Functional Diagram of VIRUS. Types Of VIRUS. Methods Of Detecting Virus By ANTI-VIRUS. Prevention.
- 4. COMPUTER VIRUS: A computer virus is a program or piece of code that is loaded onto your computer without your knowledge and run against your wish. A virus is illegal computer code that can do such things as alter programs or destroy data. Also, the virus can copy itself onto programs, thereby spreading its damaging effects.
- 5. Similarities between Biological virus and Computer virus: • Computer virus are called viruses because they share some of the traits of biological. • Viruses. A computer virus passed from computer to computer like a biological virus passes from person to person • Need a host for residence. • Capable of self-replicate. • Cause damage to host.
- 6. How does a virus work? How Does A VIRUS Spread. first the virus is linked to the host object in such a way that it activates when the host object is used. Second virus looks for other suitable carrier objects and attaches itself to them. With this dependency virus slows down the system.
- 7. A typical lifecycle of a computer virus The virus waits until user transmits the infected object to another computer User transmits an infected object to another computer The virus locates and infects suitable objects on the new computer
- 8. Functional Diagram Of Virus Virus ANTIDETECTIN ROUTINES COPY SEARCH
- 9. TYPES OFVIRUS MACROVIRUS. BOOT SECTORVIRUS. WORMS. TROJEN HORSES. LOGIC BOMBS.
- 10. A Macro virus is associated with application software like word and excel. When opening the infected document, macro virus is loaded into main memory and destroys the data stored in hard disk. MACRO VIRUS:
- 11. A boot sector virus infects boot sector of computers. During system boot, boot sector virus is loaded into main memory and destroys data stored in hard disk. A boot sector virus is a type of virus that infects the boot sector of floppy disks or the Master Boot Record (MBR) of hard disks (some infect the boot sector of the hard disk instead of the MBR). BOOT SECTOR VIRUS
- 12. A worm is also a destructive program that fills a computer system with self-replicating information. Types of WORMS VIRUS: MAIL WORM PURE WORM WORMS
- 13. Trojan Horse is a destructive program. It usually pretends as computer games or application software. If executed, computer system will be damaged. A Trojan horse or Trojan is a type of malware that is often disguised as legitimate software. Trojans can be employed by cyber-thieves and hackers trying to gain access to users' systems. Users are typically tricked by some form of social engineering into loading and executing Trojans on their systems. TROJAN HORSE
- 14. LOGICAL BOMBS • A logical bomb is a destructive program that performs an activity when a certain action has occurred. • A logic bomb is a piece of code inserted into an operating system or software application that implements a malicious function after a certain amount of time, or specific conditions are met. • Logic bombs are often used with viruses, worms, and Trojan horses to time them to do maximum damage before being noticed.
- 15. OTHERS Time Bomb Script Virus Directory Virus
- 16. BEHAVIOR -BASED DETECTION: Observe how the program execute in the computer Rather than looking for signature . Check the suspicious file and show warnings to the user. METHODS OF DETECTING THE VIRUS BY ANTIVIRUS
- 17. METHODS OF DETECTING THE VIRUS BY ANTIVIRUS Heuristic -Based Detection : Detect and remove all threats. Create a generic signature.
- 18. PREVENTION Don't share Drive C: without a password and without read-only restrictions. Delete e-mail file attachments. Use Anti-Virus. Have multiple backups of important files. More secure operating systems e.g. UNIX