Shock Therapy Virus

Virus Name: Shock Therapy Aliases: V Status: Rare Discovered: April, 1993 Symptoms: .COM & .EXE growth; decrease in total system & available free memory Origin: Unknown Eff Length: 620 Bytes Type Code: PRtAK - Parasitic Resident .COM & .EXE Infector Detection Method: AVTK, F-Prot, ViruScan, Sweep, IBMAV, NAV, NAVDX, VAlert, PCScan, NShld, Sweep/N, NProt, AVTK/N, NAV/N, IBMAV/N, LProt Removal Instructions: Delete infected files General Comments: The Shock Therapy virus was submitted in April, 1993. Its origin or point of isolation is unknown. Shock Therapy is a memory resident infector of .COM and .EXE programs, including COMMAND.COM. When the first Shock Therapy infected program is executed, the Shock Therapy virus will install itself memory resident at the top of system memory but below the 640K DOS boundary, moving interrupt 12's return. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 2,048 bytes. Interrupt 21 will be hooked by Shock Therapy in memory. Once the Shock Therapy virus is memory resident, it will infect .COM and .EXE programs, including COMMAND.COM, when they are executed. Infected programs will have a file length increase of 620 bytes with the virus being 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 strings are encrypted within the Shock Therapy virus, thus not visible within infected files: "Your HD is TOAST!Thanx to Shock Therapy!" "SHOCK THERAPY" "TIaMaT" It is unknown what Shock Therapy does besides replicate. See: PS-MPC