Ozzy Virus

Virus Name: Ozzy Aliases: Ozzy.546 V Status: New Discovered: January, 1996 Symptoms: .COM & .EXE file growth; decrease in available free memory Origin: Unknown Eff Length: 546 - 560 Bytes Type Code: PRhAK - Parasitic Resident .COM & .EXE Infector Detection Method: AVTK, IBMAV, ViruScan, NAV, NAVDX, ChAV, NAV/N, AVTK/N, NShld 2.33+ Removal Instructions: Delete infected files General Comments: The Ozzy virus was received in January, 1996. Its origin or point of isolation is unknown. Ozzy is a memory resident infector of .COM and .EXE files, including COMMAND.COM. When the first Ozzy infected program is executed, this virus will install itself memory resident at the top of system memory but below the 640K DOS boundary, not moving interrupt 12's return. Available free memory, as indicated by the DOS CHKDSK program from DOS 5.0, will have decreased by 624 bytes. Interrupts 21 and 22 will be hooked by the virus in memory. Once the Ozzy virus is memory resident, it will infect .COM and .EXE files when they are executed. Infected .COM files will increase in size by 546 bytes while .EXE files increase in size by 546 to 560 bytes. In both cases, the virus will be located at the end of the file. The program's date and time in the DOS disk directory listing will not be altered. The following text string is visible within the viral code: "Ozzy Osbourne virus por El Flaco"