Carfield Virus

Virus Name: Carfield Aliases: V Status: Rare Discovery: 1991 Symptoms: .COM & .EXE growth; TSR; message Origin: Eff Length: 1,508 - 1,522 Bytes Type Code: PRsA - Parasitic Resident .COM & .EXE Infector Detection Method: ViruScan, F-Prot, Sweep, NAV, AVTK, IBMAV, NAVDX, VAlert, PCScan, ChAV, NShld, Sweep/N, LProt, Innoc, NProt, IBMAV/N, AVTK/N, NAV/N Removal Instructions: Delete infected files General Comments: The Carfield virus was received from the NCSA in September, 1991. Its date of discovery and original isolation point are unknown. Carfield is a memory resident infector of .COM and .EXE files. It does not infect COMMAND.COM. This virus is based on the Sunday virus. The first time a program infected with Carfield is executed, the virus will install itself memory resident as a low system memory TSR of 1,744 bytes. The virus will have hooked interrupt 21. Once Carfield is memory resident, it will infect .COM and .EXE programs, other than COMMAND.COM, when they are executed. Infected .COM programs will increase in size by 1,508 bytes with the virus being located at the beginning of the infected file. Infected .EXE programs will increase in size by 1,508 to 1,522 bytes with the virus being located at the end of the infected file. There will be no change to the infected program's date and time in the DOS disk directory. The Carfield virus activates on Mondays. It will hook interrupt 08 in addition to interrupt 21 when it becomes memory resident. It will then occassionally display the text string "Carfield!" while it is memory resident. See: Sunday