A computer virus is a computer program that can copy itself and infect a computer without permission or knowledge of the .. Računalni je virus mali softverski program koji se širi s jednog računala na drugo i ometa rad računala. Računalni virus može oštetiti ili izbrisati. Koliko virusi mogu biti opasni, govori i slučaj iz godine kada je kompjuterski virus Staksnet napravio haos u svetu i uspeo da ugrozi i iranski nuklearni.
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Instrument engineers’ handbook 3rd ed. Restore points from previous days should work, provided the virus is not designed to corrupt the restore files and does not exist in previous restore points.
Computer virus – Wikipedia
Retrieved 24 July COM filesdata files such as Microsoft Word documents or PDF filesor in the boot sector of the host’s hard drive or some combination of all of these. Crna Gora – Srpski. This is because malicious hackers and other individuals are always creating new viruses. Each infected program will now contain a clone of the virus, which will itself enter a propagation phase. Ransomware and phishing scam alerts appear as press releases on the Internet Crime Complaint Center noticeboard. Ina program called ” Elk Cloner ” was the first personal computer virus to appear “in the wild”—that is, outside the single computer or [computer] lab where it was created.
Infection mechanism also called ‘infection vector’is how the virus spreads or propagates. For example, a virus can be programmed to mutate only slightly over time, or it can be programmed to refrain from mutating when it infects a file on a computer that already contains copies of the virus.
Retrieved November 28, The vast majority of viruses target systems running Microsoft Windows.
Some websites—like Google subsidiary VirusTotal. Computer and network surveillance Operation: Archived from the original on 20 December Archived from the original on July 7, The giant black book of computer viruses. This approach does not fool antivirus softwarehowever, especially those which maintain and date cyclic redundancy checks on file changes. Archived PDF from the original on Virus signatures are just strings kompjutegski code that are used to identify individual viruses; for each virus, the antivirus designer tries to choose a unique signature string that will not be found in a legitimate program.
Because those files have many empty gaps, the virus, which was 1 KB in length, did not add to the size of the file. Intrusion Prevention, Detection, and Recovery. That is, each infected file contains a different variant of the virus. Bosna i Hercegovina – Hrvatski. Idite na web-mjesto Microsoft Security Essentials. Some viruses trick antivirus software by intercepting its requests to the Operating system OS.
Sprječavanje i uklanjanje virusa i drugog zlonamjernog softvera
Polymorphic code was the first technique that posed a serious threat to virus scanners. Virus writers use oompjuterski engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect systems and to spread the virus.
The Gammima virus, for example, propagates via removable flash drives. Some viruses spread by infecting programs stored on kompjuetrski disks, while others installed themselves into the disk boot sectorensuring that they would be run when the user booted the computer from the disk, usually inadvertently.
It can be destructive such as deleting files on disk, crashing the system, or corrupting files or relatively harmless such as popping up humorous or political messages on screen.
In order to replicate itself, a virus must be permitted to execute code and write to memory. On its 50th use the Elk Cloner virus would kkompjuterski activated, infecting kompjutterski personal computer and displaying a short poem beginning “Elk Cloner: Many users install antivirus software that can detect and eliminate known viruses when the computer attempts to download or run the executable file which may be distributed as an email attachment, or on USB flash drivesfor example.
New Zealand – English. The program with a personality. Many common applications, such as Microsoft Outlook and Microsoft Wordallow macro programs to be embedded in documents or emails, so kompjutwrski the programs may be run automatically when the document is opened. Phishing is a deception in which the malicious individual pretends to be a friend, computer security expert, or other benevolent individual, with the goal of convincing the targeted individual to reveal passwords viruwi other personal information.
Different antivirus programs will employ different search strings, and indeed different search methods, when identifying viruses.
However, not all viruses carry a destructive “payload” and attempt to hide themselves—the defining characteristic of viruses is that they are self-replicating computer programs which modify other software without user consent. Uses authors parameter CS1 maint: A well-written polymorphic virus therefore has no parts which remain identical between infections, making it very difficult to detect directly using “signatures”.
Retrieved June 10, To avoid being detected by emulation, some viruses rewrite themselves completely each time they are to infect new executables.
Archived from the original on September 6, One may reduce the damage done by viruses by making regular backups of data and the operating systems on different media, that are either kept unconnected to the system most of the time, as in a hard driveread-only or not accessible for other reasons, such as using different file systems. Software development strategies that produce large numbers of “bugs” will generally also produce potential exploitable “holes” or “entrances” for the virus.
Security software can then be used kompjutegski check the dormant operating system files. Email virus — A virus that intentionally, rather than accidentally, uses the email system to spread.