Day10 Virus

Virus Name: Day10 Aliases: Day/10, SYP V Status: Rare Discovered: November, 1991 Symptoms: .COM file growth; file date/time change; hard disk corruption Origin: Unknown Eff Length: 674 Bytes Type Code: PNCK - Parasitic Non-Resident .COM Infector Detection Method: ViruScan, AVTK, Sweep, F-Prot, ChAV, NAV, IBMAV, NAVDX, VAlert, PCScan, NShld, LProt, Sweep/N, Innoc, AVTK/N, IBMAV/N, NAV/N Removal Instructions: Delete infected files General Comments: The Day10 virus was received in November, 1991. Its origin is unknown. Day10 is a non-resident, direct action infector of .COM programs, including COMMAND.COM. It is destructive when it activates. When a program infected with the Day10 virus is executed, the virus will infect one .COM program located in the current directory. If COMMAND.COM is located in the current directory, it may become infected. Day10 infected programs will have a file length increase of 674 bytes. The virus will belocated at the end of the infected file. The file's date and time in the DOS disk directory will also have been updated to the system date and time when infection occurred. The following text string can be found within the viral code in infected programs: "DM?COM#" Day10 activates when an infected program is executed if the system date is evenly divisible by 10 (day=10, 20, or 30). On these days, execution of an infected program will result in the Day10 virus overwriting the first 80 sectors of the system hard disk.