1241 Virus

Virus Name: 1241 Aliases: V Status: Rare Discovery: December, 1991 Symptoms: .COM file growth; TSR Origin: Unknown Eff Length: 1,241 Bytes Type Code: PRsCK - Parasitic Resident .COM Infector Detection Method: ViruScan, F-Prot, AVTK, NAV, Sweep, IBMAV, NAVDX, VAlert, PCScan, ChAV, NShld, Sweep/N, LProt, Innoc, NProt, AVTK/N, NAV/N, IBMAV/N Removal Instructions: Delete infected files General Comments: The 1241 virus was received in December, 1991. Its origin is unknown. This virus is a memory resident infector of .COM programs, including COMMAND.COM. When the first 1241 infected program is executed, the 1241 virus will install itself memory resident as a low system memory TSR of 1,584 bytes, hooking interrupt 21. Its TSR may appear as "Command data" or as part of the command interpretor in some memory mapping utilities. Once the 1241 virus is memory resident, it will infect .COM programs when they are executed. If COMMAND.COM is executed, it will become infected as well. 1241 infected files will have a file length increase of 1,241 bytes with the virus being located at the end of the infected file. There will be no change to the file's date and time in the DOS disk directory listing. It is unknown what 1241 does besides replicate.