439 Virus

Virus Name: 439 Aliases: Beech V Status: Rare Discovery: August, 1992 Symptoms: .COM file growth; decrease in total system & available free memory Origin: Poland Eff Length: 439 Bytes Type Code: PRhCK - Parasitic Resident .COM Infector Detection Method: F-Prot, Sweep, ViruScan, IBMAV, AVTK, NAV, NAVDX, VAlert, PCScan, ChAV, NShld, Sweep/N, Innoc, NProt, AVTK/N, LProt, NAV/N, IBMAV/N Removal Instructions: Delete infected files General Comments: The 439 virus was received in August, 1992. It is originally from Poland. 439 is a memory resident infector of .COM programs, including COMMAND.COM. The first time a program infected with the 439 virus is executed, the 439 virus will install itself memory resident at the top of system memory but below the 640K DOS boundary. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 2,064 bytes. Interrupt 21 will be hooked by the virus in memory. Once the 439 virus is memory resident, it will infect .COM programs, including COMMAND.COM, when they are executed or opened. Infected programs will have a file length increase of 439 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 not be altered. The 439 virus doesn't appear to do anything besides replicate. Known variant(s) of 439 are: 439-B: Functionally equivalent to the original virus, 439-B is a minor variant. A couple bytes differ from the original. Origin: Poland September, 1992.