Boojum Virus

Virus Name: Boojum Aliases: V Status: Rare Discovery: May, 1992 Symptoms: .EXE file growth; decrease in total system & available free memory Origin: Unknown Eff Length: 340 - 350 Bytes Type Code: PRhE - Parasitic Resident .EXE Infector Detection Method: ViruScan, Sweep, AVTK, F-Prot, ChAV, NAV, IBMAV, NAVDX, VAlert, PCScan, NShld, Sweep/N, Innoc, NProt, AVTK/N, NAV/N, IBMAV/N, LProt Removal Instructions: Delete infected files General Comments: The Boojum virus was received in May, 1992. Its origin or point of isolation are unknown. Boojum is a memory resident infector of .EXE programs. When the first program infected with the Boojum virus is executed, the Boojum virus will install itself memory resident at the top of system memory but below the 640K DOS boundary. Interrupt 12's return will not be moved. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 368 bytes. Interrupt 21 will be hooked by Boojum in memory. Once the Boojum virus is memory resident, it will infect .EXE programs when they are executed. Infected programs will have a file length increase of 340 to 350 bytes with the virus being located at the end of the infected file. The program's date and time in the DOS disk directory listing will not be altered. No text strings are visible within the viral code in Boojum infected programs. Boojum doesn't do anything besides replicate.