How Can This Be Used?
Now we need to figure out what's really going on. To create the buffer overflow situation, I created a file called "overflow.cnf". CNF is a file format used by Microsoft Netmeeting when you save a 'SpeedDial' shortcut to disk. CNF files are commonly placed on people's webpages and in emails so that people on netmeeting will give them a call.
If you wanted to exploit this overflow, you could simply start up Netmeeting, find a bunch of people on the ILS server, and send them email with the CNF file attached. Just make the mail say something like: My girlfriend and I want you to watch us fuck while you spank it! Call us soon, we're horny! They'll click the icon. It may also be possible to fake a connection to an ILS server as well, creating a fake user and supplying the bogus address line with our exploit it in, so that if they click on the name, they get zapped. All kinds of fun owning the machines of horny men looking for titties on the net!
So. Let's do it! What do we have at our disposal? Well, the overflow is in 'RUNDLL32.EXE', which is of different sizes between Windows 95 and Windows NT. It's a safe bet to assume that they have different import tables (go ahead and verify that yourself with DUMPBIN). Oh, by the way, this particular overflow will only happen in Windows 95, but the exploit technology is valid for Windows NT as well. Netmeeting 2.1 was the version, by the way.