Che Gueva Virus

Virus Name: Che Gueva Aliases: Che Gueva.1918 V Status: New Discovery: July, 1996 Symptoms: .COM & .EXE file growth; decrease in available free memory Origin: Spain Eff Length: 1,918 - 1,934 Bytes Type Code: PRhA - Parasitic Resident .COM & .EXE Infector Detection Method: NAV, NAVDX, ViruScan, AVTK 7.68+, NAV/N, NShld 2.33+, AVTK/N 7.68+ Removal Instructions: Delete infected files General Comments: The Che Gueva virus was received in July, 1996. It is from Spain, and may be "in the wild" in that country. Che Gueva is a memory resident infector of .COM and .EXE file, but not COMMAND.COM. It does not infect small .COM and .EXE files. When the first Che Gueva 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 2,400 bytes. Interrupt 21 will be hooked by the virus in memory. Once the Che Gueva virus is memory resident, it will infect .COM and .EXE files, other than small ones and COMMAND.COM, when they are executed. Infected .COM files will have a file length increase of 1,918 bytes while .EXE files increase in size by 1,918 to 1,934 bytes. In both cases, the virus will be 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: "VHR?" "K\*LVY[_OKNY" "*K*M_LK" "KWZYMY**********" "PSX*NOV*LVY[_OY*K*M_**" "EHC" It is unknown what this virus may do besides replicate.