P&C Virus

Virus Name: P&C Aliases: P&C.855 V Status: New Discovery: July, 1995 Symptoms: .COM file growth; system hangs; decrease in available free memory Origin: Unknown Eff Length: 855 Bytes Type Code: PRhCK - Parasitic Resident .COM Infector Detection Method: F-Prot, AVTK, VAlert, Sweep, NAV, NAVDX, IBMAV, ViruScan, ChAV, Sweep/N, NAV/N, IBMAV/N, NShld, AVTK/N, Innoc 4.0+ Removal Instructions: Delete infected files General Comments: The P&C virus was received in July, 1995. Its origin or point of isolation is unknown. P&C is a memory resident infector of .COM programs, including COMMAND.COM. System hangs may occur when the virus infects very small .COM files. When the first P&C 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 928 bytes. Interrupt 21 will be hooked by the virus in memory. Once the P&C virus is memory resident, it will infect .COM files, including COMMAND.COM, when they are executed. Infected .COM files will have a file length increase of 855 bytes with the virus being located at the end of the file. The file's date and time in the DOS disk directory listing will not be altered. The following text string is visible within the viral code: "P&C" This text string can also be found starting in the fourth byte of all infected files.