Chemmy Virus


 Virus Name:  Chemmy 
 Aliases:    
 V Status:    Rare 
 Discovery:   February, 1992 
 Symptoms:    .COM & .EXE growth; decrease in total system & available free 
              memory 
 Origin:      Unknown 
 Eff Length:  1,691 - 1,706 Bytes 
 Type Code:   PRhAK - Parasitic Resident .COM & .EXE Infector 
 Detection Method:  ViruScan, AVTK, F-Prot, Sweep, IBMAV, ChAV, 
                    NAV, NAVDX, VAlert, PCScan, 
                    Sweep/N, NShld, Innoc, AVTK/N, IBMAV/N, NAV/N, LProt 
 Removal Instructions:  Delete infected files 
 
 General Comments: 
       The Chemmy virus was received in February, 1992.  Its origin is 
       unknown.  Chemmy is a memory resident infector of .COM and .EXE 
       programs, including COMMAND.COM. 
 
       When the first Chemmy infected program is executed, the Chemmy 
       virus installs 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 3,392 bytes.  Interrupt 12's return will not have been moved. 
       Interrupt 22 will be hooked by the Chemmy virus in memory. 
 
       After the Chemmy virus is memory resident, it will infect .COM and 
       .EXE programs when they are copied.  The source file will not be 
       infected, only the target becomes infected.  Programs infected with 
       the Chemmy virus will have a file length increase of 1,691 to 
       1706 bytes with the virus being located at the end of the infected 
       program.  The file's date and time in the DOS disk directory listing 
       will not be altered. 
 
       Chemmy is an encrypted virus, and no text strings are visible within 
       the viral code in infected programs. 
 
       It is unknown what Chemmy may do besides replicate. 
 
       Known variant(s) of Chemmy are: 
       Chemmy-B: Chemmy-B is a minor variant of the Chemmy virus, and 
                 is functionally equivalent. 
                 Origin:  Unknown  February, 1992. 
 
       See:   Cheeba 

Show viruses from discovered during that infect .

Main Page