Yukon Overwriting Virus

Virus Name: Yukon Overwriting Aliases: V Status: Viron Discovered: January, 1991 Symptoms: Divide Overflow errors; beginning of programs overwritten Origin: Canada Eff Length: 151 Bytes Type Code: ONCK - Overwriting Non-Resident .COM Infector Detection Method: F-Prot, Sweep, AVTK, ViruScan, ChAV, NAV, IBMAV, NAVDX, VAlert, PCScan, NShld, Sweep/N, LProt, Innoc, NProt, AVTK/N, IBMAV/N, NAV/N Removal Instructions: Delete infected files General Comments: The Yukon Overwriting virus was isolated in January, 1991 in Canada. This virus is a non-resident overwriting virus that infects .COM files, including COMMAND.COM. When a program infected with the Yukon Overwriting virus is executed, the virus will infect all .COM programs in the current directory. Infected programs will have the first 151 bytes of the program overwritten with the virus. Their date and time in the disk directory will not be altered in the process of infection. After infecting all of the .COM files in the current directory, the program the user was attempting to execute will fail with a Divide Overflow error. Infected programs can be easily identified because the text string Divide Overflow$ will be located beginning at offset 87h within the infected program. Programs infected with the Yukon Overwriting virus cannot be disinfected as the portion overwritten by the virus is not stored. Infected programs must be deleted and replaced with uninfected copies.