What is a Crypter?
Well,Before we get into the good stuff, lets first clear up all your questions you have been having by really getting into all the fundamentals of Crypters. Oh and if you have any questions of anything throughout this tutorial, just post here. If you don't already know, A Crypter is usually used to encrypt files like viruses, rats, keyloggers or it can be any type of file which you want to protect usually for the sole purpose of bypassing antivirus detection.
What's the difference between a Crypter and a Packer?
A Crypter Encrypts your files, while a Packer packs your files usually with the intention of making it smaller in size and sometimes for it to be undetectable on virus scans.
What's the difference between a Runtime and Scantime Crypter?
Both can look exactly the same so you better watch out..
-A Runtime Crypter encrypts the specified file and when executed (ran), it is decrypted in memory. This way antiviruses aren’t able to analyse the file before executed and after executed.
-A Scantime Crypter encrypts the specified file so antiviruses aren’t able to analyse the file only before executed but NOT when executed.
How do i know which antiviruses detect my file?
There are many sites with this same purpose of scanning files and giving a report of which antiviruses detect your files. The main issue leading to Crypters becoming detected is because if you or someone who is in posession of your crypted file, scans it on some of these scanner sites, the crypted file will be distributed to the antivirus vendors, thus causing the crypted code overwritten on your file to become detected, which in turn causes your Crypter to turn out detected. I recommend that you scan your files on http://www.novirusthanks.org - But MAKE SURE the "Do not distribute sample" check box is checked
What is EOF and what is it used for?
EOF stands for End Of File. Some files like Bifrost, Medusa, and Cybergate require the end of file data in order to run without corruption. So If Crypters don’t preserve this end of file data, your crypted file will become corrupt.
What is a USG?
A USG is part of a crypter that generates a unique version of the stub (stub is part of a crypter used to encrypt and decrypt the specified file). The purpose of this is because FUD crypters don’t last forever, eventually crypters become detected over a period of time. You will understand this better later on in the tutorial.
What is a File Binder?
A File Binder is pretty self explanatory. It “binds” or puts 2 files together as one so as a result when someone opens this one file, 2 files will execute. You would usually use a file binder when being even more stealth then just simply a crypted file. The biggest question people have when first learning what a binder is and what it does is, can you bind a .exe with something different? like a .jpg for example? The answer is Yes, BUT.. the output of both binded files will be shown as .exe, so in a way it can defeat the purpose.
What are "Antis" on Crypters?
Anti’s are an extra feature that come with some Crypters. For example anti-vm, anti-debugger, anti-avira...etc. These refer to bypassing or preventing something specified, so anti-debugger meaning it will prevent it from being debugged.
What is a File Pumper?
A File Pumper will “pump” your file - referring to adding more bytes to it making your file larger. The benefit of this is usually not so great but it can be okay to have and may lose a detection or 2.
Types and Forms of Crypters
Crypters can range in many types and forms and it is important to understand these types and forms because it will help you choose a quality crypter to solve your needs or help you realize what options and features you would want to implement in your own Crypter.
The Most IMPORTANT Factors You Should Know
As I'm sure many of you know, finding Crypters and Crypters themselves can be a huge pain. I know when i first started out, I hated the fact that i just couldn’t find a FREE FUD CRYPTER anywhere. I got so pissed, but didn’t give up just yet. I kept on searching and reading a diverse range of forums. Overtime, once I learned enough about them i realized the actual undetection vs antivirus concept. This is the eye opener point which you will all eventually end up and at this point you will then realize why.
This Guide is fully not written by me but I got the permission to share this who wrote it. Thank you!! :) And if you need any kind of help in Crypter then just post here and I'll get back to you. :)