PPSP Virus

Virus Name: PPSP Aliases: PPSP.1526 V Status: Rare Discovered: December, 1994 Symptoms: .COM file growth; decrease in total system and available free memory Origin: Unknown Eff Length: 1,528 - 1,541 Bytes Type Code: PRhCK - Parasitic Resident .COM Infector Detection Method: AVTK, ViruScan, Sweep, NAV, NAVDX, VAlert, ChAV, AVTK/N, Sweep/N, NShld, Innoc, NAV/N Removal Instructions: Delete infected files General Comments: The PPSP or PPSP.1526 virus was received in November, 1994. Its origin or point of isolation is unknown. PPSP is a memory resident fast infector of .COM files, including COMMAND.COM. When the first PPSP 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. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 2,048 bytes. Interrupts are directly hooked by the virus in memory and memory mapping utilities will not indicate any interrupts hooked by the virus. Once the PPSP virus is memory resident, it will infect .COM programs, including COMMAND.COM, when they are executed or a DOS DIR command is performed. It does not, however, infect programs located in subdirectories. Infected programs will have a file length increase of 1,528 to 1,541 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 visible within the viral code in all PPSP infected files: "*.COM *" "COMMAND.COM" "PP" "SP" The "PP" text string will start in the second byte of all infected files. The "SP" text string will begin in the tenth byte.