Virus Simulation Suite Written by Joe Hirst
British Computer Virus Research Centre (Tel: 0273-26105)
12 Guildford Street, Brighton, East Sussex, BN1 3LS, England
(Tel: 0273-26105)

Copyright (c) Joe Hirst 1988, 1989, 1990.


These programs simulate the visual and aural effects of some of the PC viruses.

They are public service freeware, which means that they are provided as a
public service, and, although the copyright is retained, any person or company
may use them for any legitimate purpose (commercial or otherwise).

The only restrictions are that users may not attempt to alter the programs,
and they may not state or imply that they have any exclusive rights to or
control over the programs.

All of these programs will check their own length before executing, and also
perform a checksum test for corruption. If either of these tests fails the
program will refuse to execute.

The complete set of programs currently consists of:

CASC-SIM.COM Cascade virus (standard activation)
CSC-SIMX.COM Cascade virus (display only)
DENZ-SIM COMDenzuk virus - single shot display
FUMN-SIM.COM Jerusalen (2) (Fu Manchu) virus
FUM-SIMD COMJerusalen (2) (Fu Manchu) virus - single shot display
FUM-SIMX.COM Jerusalen (2) (Fu Manchu) virus (censored)
ITAL-SIM.COM Italian virus (standard activation)
ITL-SIMX.COM Italian virus (display only)
JERU-SIM.COM Jerusalem (1) virus
OROP-SIM.COM Music virus
ORO-SIMX.COM Music virus (minimum delay)
YANK-SIM.COM Yankee Doodle virus (standard activation)
YNK-SIMX.COM Yankee Doodle virus (display only)

Many of these programs are TSRs, and in all such cases the program can be
removed from memory by the <-> key combination.

Some of them have a programmable builtin delay, and these may be called with
a numeric parameter between 1 and 30 inclusive. This number represents the
delay in minutes before displaying the simulation effect. If the program is
called without a parameter a delay of one minute is assumed, except for the
program ITL-SIMX where no parameter means no delay.

In many cases the simulation can be switched off, and the delay reset,
by the <+> key combination. The exception is the program ITL-SIMX when
called without a parameter: in this case the <+> key combination toggles
the display.

Please note that the <+> & <-> refer to the grey keys right of the numeric
key pad.

CASC-SIM.COM
Cascade virus (standard activation)

This program simulates the display of the Cascade virus. Characters will
fall down the screen until they encounter another character or a change in
the background or foreground colours.

The area of display affected will initially be one column. This will build
up with successive displays until the full screen is affected.

The delay before the first display will be random with a maximum of five
minutes, and that between displays will be random with a maximum of one
minute.

CSC-SIMX.COM [n]
Cascade virus (display only)

This program simulates the display of the Cascade virus, but with a controlled
delay. Characters will fall down the screen until they encounter another
character or a change in the background or foreground colours.

The area of display affected will be the full-screen.

The delay before the first display, and that between displays, will be equal
to the entered parameter in minutes, or one minute if no parameter is given.

DENZ-SIM.COM
Denzuk virus - single shot display

This program is not a TSR, nor does it accept any parameters. It duplicates
the visual display produced by the virus when Ctrl-Alt-Del is intercepted.

FUMN-SIM.COM
Jerusalen (2) (Fu Manchu) virus

The virus intercepts the keyboard I/O interrupt, and certain words cause the
addition of comments. These comments go into the keyboard buffer, not just on
the screen.

The trigger words include "Thatcher", "Botha", "Reagan", "Waldheim" and
"Fu Manchu". In each case the trigger is the word (or words) followed by a
space. The other trigger words are the two more explicit four-letter words
(without a space). Be warned that this simulation, like the virus, uses
explicit language.

Ctrl-Alt-Del is intercepted and produces a message before the machine reboots.

There is no reset with this program.

FUM-SIMD.COM
Jerusalen (2) (Fu Manchu) virus - single shot display

This program is not a TSR, nor does it accept any parameters. It displays the
message produced by the virus when Ctrl-Alt-Del is intercepted.

FUM-SIMX.COM
Jerusalen (2) (Fu Manchu) virus (censored)

This program is exactly as described for FUMN-SIM.COM, except that the two
four-letter words have been censored to "c***" and "f***", both on input and
output.

This version is intended for public demonstrations where it is felt that the
full-blooded version would be inappropriate.

ITAL-SIM.COM
Italian virus (standard activation)

This program simulates the display of the Italian virus, which is a single
character "bouncing ball".

The display will only activate under the same condition as the real virus,
which is a disk access during a one second time "window" occurring every half
hour. "Reset" will switch off the display again until the next such
activation.

ITL-SIMX.COM [n]
Italian virus (display only)

This program simulates the display of the Italian virus, which is a single
character "bouncing ball".

If called with a parameter there will be a delay before the display is
activated equal to the parameter in minutes. Reset will switch off the
display until this same delay has elapsed again.

If called without a parameter the display will appear immediately, and reset
will switch the display on and off

JERU-SIM.COM [n]
Jerusalem virus

This program simulates Jerusalem virus. After the initial delay a portion
of the screen (from row 5 column 5 to row 16 column 16) will be scrolled up
two lines, creating a small black gap in the display. At this time a time
wasting loop will be activated, and the processor will appear to be slowed
down. Reset will switch off the slow-down effect, and re-institute the delay.

If called with a parameter there will be a delay before the display is
activated equal to the parameter in minutes. If called without a parameter,
the delay will be one minute. Reset will switch off the display until this
same delay has elapsed again.

OROP-SIM.COM
Music virus

This program simulates audible effect of the Music virus. After an initial delay of five
minutes it will start playing its cycle of three tunes, with a seven minute
delay between tunes.

This will continue until the machine is re-booted, or the program is removed
from memory.

ORO-SIMX.COM
Music virus (minimum delay)

This program simulates audible effect of the Music virus. The simulation is the same as OROP-SIM
above, except that the five and seven minute delays have been changed to one
second and half a minute respectively.

YANK-SIM.COM
Yankee Doodle virus (standard activation)

This program simulates the audible effect of the Yankee Doodle virus, which
is the tune "Yankee Doodle".

The tune will only activate under the same condition as the real virus,
which is at approximately 17.00 hours (five p.m.).

YNK-SIMX.COM [n]
Yankee Doodle virus (tune only)

This program simulates the audible effect of the Yankee Doodle virus, which
is the tune "Yankee Doodle".

If called with a parameter there will be a delay before the tune is activated
equal to the parameter in minutes. If called without a parameter, the delay
will be one minute.