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Glossary

Companion Virus

Companion viruses use a feature of DOS that allows software programs with the same name, but with different extensions, to operate with different priorities. Most companion viruses create a COM file which has a higher priority than an EXE file with the same name.
Thus, a virus may see a system contains the file PROGRAM.EXE and create a file called PROGRAM.COM. When the computer executes PROGRAM from the command line, the virus (PROGRAM.COM) runs before the actual PROGRAM.EXE. Often the virus will execute the original program afterwards so the system appears normal.

 

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- ZIP File

- Worm

- Windows Scripting

- Warm Boot

- Virus Hoaxes

- Virus

- Variant

- Vaccination

- VBS

- Tunneling

- Trojan Horse Program

- Triggered Event

- Timestamp

- Time Bomb

- TSR

- System Boot Record

- Stealth Virus

- Sparse Infector

- Sniffer

- Slow Infector

- Signature

- Shareware

- Shared Drive

- Self-garbling Viruses

- Self-extracting Files

- Self-encrypting Virus

- Sector Viruses

- Scanner

- SMTP

- Resident Virus

- Replication

- Redirect

- Real-time Scanner

- RTF File

- Program Infector

- Polymorphic Virus

- Piggyback

- Payload

- Password Sniffing

- Password Attacks

- PGP

- Overwriting Virus

- Operating System

- On-demand Scanner

- On-access Scanner

- Not In The Wild

- NTFS

- Mutating Virus

- Mutant

- Multipartite Virus

- Memory-resident Virus

- Master Boot Sector Virus

- Master Boot Sector

- Master Boot Record

- Malware

- Malicious Code

- Macro Virus

- Macro

- MS-DOS

- MP3 File

- MBR

- Logic Bomb

- Library File

- Key

- Joke Programs

- JavaScript

- Infection

- Host

- Hole

- Hijacking

- Heuristic Analysis

- Firewall

- File Viruses

- FAT

- Encryption

- Encrypted Virus

- EXE file

- Dropper

- Disinfection

- Direct Action Virus

- Denial Of Service (DoS)

- DOS

- Cookie

- Companion Virus

- Cold Boot

- Cluster Virus

- Checksum

- Boot Sector Infector

- Boot Sector

- Boot Record

- Boot

- Batch files

- Backup

- Background Task

- Background Scanning

- Back Door

- BIOS

- Antivirus Virus

- Anti-virus Software