Pyramid Virus

Virus Name: Pyramid Aliases: V Status: New Discovery: July, 1995 Symptoms: .COM file growth; file date/time changes Origin: Unknown Eff Length: 457 - 465 Bytes Type Code: PRaCK - Parasitic Resident .COM Infector Detection Method: F-Prot, AVTK, Sweep, NAV, NAVDX, ViruScan, IBMAV, ChAV, Sweep/N, NAV/N, NShld, AVTK/N, IBMAV/N, Innoc Removal Instructions: Delete infected files General Comments: The Pyramid virus was received in July, 1995. Its origin or point of isolation is unknown. Pyramid is a memory resident infector of .COM files, including COMMAND.COM. When the first Pyramid infected program is executed, this virus will install itself memory resident in allocated system memory. Total system and available free memory, as indicated by the DOS CHKDSK program, will not be altered. Interrupt 21 will be hooked by the virus in memory. Once the Pyramid virus is memory resident, it will infect .COM files when they are executed, opened, or copied. Infected files will have a file length increase of 457 to 465 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 have been updated to the current system date and time when infection occurred. No text strings are visible within the viral code.