can u suggest me the popular torjan used now a days that are been undectable or can operate smoothly ?like kinda back doors....
It's called a trojan. Short for Trojan Horse - lookup the history of Troy for the original idea. Probably you'll need to participate in underground illicit cracker/script kiddie groups to find this sort of stuff out; it's certainly nothing to do with ETHICAL (look it up in the dictionary) hacking.
I'm not sure I would classify this as totally black hat... I can see a few ethical purposes for undetectable trojans. As far as trojans go, subseven is hard to beat, but it's also detected by most malware scanners. You won't find much code that will do what you need without being recognized by those scanners without visiting underground sites (no, I'm not going to list any here). You might be better off going with a known trojan if you can't make your own and just obfuscating its signature (search these forums for a how-to). Either way, you're probably not going to get anywhere without a solid knowledge of coding techniques and hex editing, etc.
> I can see a few ethical purposes for undetectable trojans. Such as what? If you're doing stuff on computers you've been permitted access to, then you don't need a trojan to do what you want to do. If you "just want to do it that way" then you don't need an undetectable trojan; any will do; just disable the virus checker until you're done.
Such as anything falling on the ethical side of gray hat hacking. It's a touchy area, but I'm more sure of it's existence than I am of its nonexistence.
> Such as anything falling on the ethical side of gray hat hacking. Yeah, but such as what specifically, as you said earlier "I can see a few ethical purposes for undetectable trojans": what purposes can you see? Or do you just mean generally you think there might be, without knowing of anything specific?
Well, here's one example. Say my email has been hacked and the hacker is using it to reset all my passwords to my other accounts. The email company naturally won't do anything about it, and it would be tough to get the law involved without the company's cooperation. This is where the ethical side of gray hat hacking comes into play. I don't think it would be outside the ethical restraints if I were to send him an undetectable keylogger so that I could get my online identity back. That's definitely a gray area, but is it unethical? If I had a lot to lose by allowing him to keep control of that address and those accounts, I would be tempted to say that no, it wouldn't be unethical. It would simply be self-defense. That's just the first example that comes to mind, anyway. Little scenarios like this make me a bit hesitant to say that ethical applications do not exist. I'll readily admit they are few and far between, but nonexistent? I'm not so sure.