Hello
What is a Crypter ?
The Crypter is a software that can encrypt the executable file (.exe).
Usually are used to encrypt, RAT virus, keyloggers, spywares and other types of malware to make them undetectable by antivirus.
The Crypter takes the original binary executable code and applies a variety of encryption. In this way it create a new executable, essentially the same as the original but with a totally "distorted" by crypter. That elude the best antivirus controls, in this case it is said that the virus became FUD (Full Undetectable).
The crypter are also software, for them is the same speech of FUD. Even the crypter, after some time, are detected by antivirus and any encrypted files from them is recognized by antivirus (but we will see at the end of the post).
What does a Crypter ?
A crypter simply encodes the source code of a virus into something that is undetectable by antivirus. There are several methods to accomplish the encryption code, and there are many cryptographic algorithms to do it.
What does it mean FUD ?
FUD is an acronym for Fully UnDetectable, or completely undetectable. With the advent of Crypter and using them to bypass the antivirus, the same softwarehouse began to include in the same antivirus definitions for the crypter, owned as potentially dangerous threats (PUP).
What types of Crypters are there ?
Crypters ScanType: encodes the specified file so that the AV are unable to analyze it, but just before it is executed. While it is possible that you may experience.
Crypters runtime: encodes the file specified and when executed, is decrypted in memory. In this way the antiviruses are not capable of to analyze it before or after his execution.
Crypter anatomy
Client:
The client is the interface which interacts with crypter functions in the manner chosen by the programmer.
Stub:
The Stub is an executable (.exe) or a. DLL. This file is used as a filter for files that are given the crypter.
EOF:
EOF : End of File. Many RAT require an EOF to run. If the Crypter does not preserve it, the file will be corrupt.
Anti's:
It is an additional feature that may have some crypters, combined with specific products. Anti-debugger, anti- vm, etc. Referring to bypass something in particular.
Hide Process:
Ensures that the encrypted file is hidden from the normal list of currently executing processes (usually visible from windows task manager).
No Dependencies:
No Dependencies means that both the crypter, both the encrypted files don't need .net framework installed on the machine to run properly.
File Binder:
It is a software used to bind or combine two or more files into a single file, with one extension.
This is only a short article but it is very important to say that this type of software is not very popular so the Crypter will have a longer life. It will take a long time before being unmasked by antiviruses : affecting a limited range of people will not have enough diffusion density.
Regards
What is a Crypter ?
The Crypter is a software that can encrypt the executable file (.exe).
Usually are used to encrypt, RAT virus, keyloggers, spywares and other types of malware to make them undetectable by antivirus.
The Crypter takes the original binary executable code and applies a variety of encryption. In this way it create a new executable, essentially the same as the original but with a totally "distorted" by crypter. That elude the best antivirus controls, in this case it is said that the virus became FUD (Full Undetectable).
The crypter are also software, for them is the same speech of FUD. Even the crypter, after some time, are detected by antivirus and any encrypted files from them is recognized by antivirus (but we will see at the end of the post).
What does a Crypter ?
A crypter simply encodes the source code of a virus into something that is undetectable by antivirus. There are several methods to accomplish the encryption code, and there are many cryptographic algorithms to do it.
What does it mean FUD ?
FUD is an acronym for Fully UnDetectable, or completely undetectable. With the advent of Crypter and using them to bypass the antivirus, the same softwarehouse began to include in the same antivirus definitions for the crypter, owned as potentially dangerous threats (PUP).
What types of Crypters are there ?
Crypters ScanType: encodes the specified file so that the AV are unable to analyze it, but just before it is executed. While it is possible that you may experience.
Crypters runtime: encodes the file specified and when executed, is decrypted in memory. In this way the antiviruses are not capable of to analyze it before or after his execution.
Crypter anatomy
Client:
The client is the interface which interacts with crypter functions in the manner chosen by the programmer.
Stub:
The Stub is an executable (.exe) or a. DLL. This file is used as a filter for files that are given the crypter.
EOF:
EOF : End of File. Many RAT require an EOF to run. If the Crypter does not preserve it, the file will be corrupt.
Anti's:
It is an additional feature that may have some crypters, combined with specific products. Anti-debugger, anti- vm, etc. Referring to bypass something in particular.
Hide Process:
Ensures that the encrypted file is hidden from the normal list of currently executing processes (usually visible from windows task manager).
No Dependencies:
No Dependencies means that both the crypter, both the encrypted files don't need .net framework installed on the machine to run properly.
File Binder:
It is a software used to bind or combine two or more files into a single file, with one extension.
This is only a short article but it is very important to say that this type of software is not very popular so the Crypter will have a longer life. It will take a long time before being unmasked by antiviruses : affecting a limited range of people will not have enough diffusion density.
Regards
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