Feist Virus
Virus Name: Feist
Aliases:
V Status: Rare
Discovered: January, 1992
Symptoms: .COM & .EXE growth; file date/time changes; unexpected error
messages
Origin: Unknown
Eff Length: 670 Bytes
Type Code: PRfAK - Parasitic Resident .COM & .EXE Infector
Detection Method: Sweep, ViruScan, F-Prot, AVTK, ChAV,
NAV, IBMAV, NAVDX, VAlert, PCScan,
NShld, LProt, Sweep/N, Innoc, NProt, AVTK/N,
NAV/N, IBMAV/N
Removal Instructions: Delete infected files
General Comments:
The Feist virus was received in January, 1992. Its origin or
point of original isolation is unknown. Feist is a memory resident
infector of .COM and .EXE programs, including COMMAND.COM.
The first time a program infected with the Feist virus is executed,
this virus will install itself memory resident in free available
memory. As such, there will be no change to total system and
available free memory. Interrupt 21 will be hooked by the virus.
Once the Feist virus is memory resident, it will infect .COM and
.EXE programs when they are executed. Infected programs will have
a file length increase of 670 bytes with the virus being located
at the end of the infected file. The program's date and time in
the DOS disk directory will have been updated to the current system
date and time. The following text string can be found within the
viral code in all Feist infected programs:
"R.Feist"
Systems infected with the Feist virus may experience unexpected
errors when attempting to execute programs. These errors include,
but are not limited to, divide overflow errors and data errors
reading or writing to the current drive.