Charm Virus

Virus Name: Charm Aliases: V Status: New Discovery: July, 1995 Symptoms: .COM file growth; file date/time changes Origin: Unknown Eff Length: 501 - 508 Bytes Type Code: PRaCK - Parasitic Resident .COM Infector Detection Method: F-Prot, AVTK, VAlert, NAV, NAVDX, ViruScan, Sweep, IBMAV, ChAV, NShld, NAV/N, Sweep/N, AVTK/N, IBMAV/N, Innoc Removal Instructions: Delete infected files General Comments: The Charm virus was received in July, 1995. Its origin or point of isolation is unknown. Charm is a memory resident infector of .COM files, including COMMAND.COM. It does not infect very small .COM files. When the first Charm infected program is executed, this virus will install itself in allocated system memory, hooking interrupt 21. Total system and available free memory, as indicated by the DOS CHKDSK program, will not be altered. Once the Charm virus is memory resident, it will infect .COM files when they are executed. Programs infected with the Charm virus will have a file length increase of 501 to 508 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 have been updated to the current system date and time when infection occurred. No text strings are visible within the viral code. It is unknown what the Charm virus may do besides replicate.