Skew-469 Virus

Virus Name: Skew-469 Aliases: Skew V Status: Rare Discovered: February, 1993 Symptoms: .EXE file growth; file date/time changes Origin: USSR Eff Length: 469 - 485 Bytes Type Code: PRxE - Parasitic Resident .EXE Infector Detection Method: Sweep, AVTK, F-Prot, IBMAV, ViruScan, NAV, NAVDX, VAlert, PCScan, ChAV, Sweep/N, NShld, AVTK/N, NAV/N, NProt, IBMAV/N, Innoc, LProt Removal Instructions: Delete infected files General Comments: The Skew-469, or Skew, virus was submitted in February, 1993, and is originally from the USSR. Skew-469 is a memory resident infector of .EXE programs. It is a fast infector, quickly spreading on infected systems. When the first Skew-469 virus infected program is executed, this virus will install itself memory resident in a "hole" in allocated low system memory, hooking interrupts 1C and 21. Total system and available free memory, as indicated by the DOS CHKDSK program, will not be altered. Once the Skew-469 virus is memory resident, it will infect .EXE programs when they are executed or opened for any reason. Infected programs will have a file length increase of 469 to 485 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 in infected programs. It is unknown if Skew-469 does anything besides replicate.