![]() A stub program containing the original, but obfuscated, executable file (often malware) within its data performs staging to prepare the embedded, obfuscated code for execution. Runtime crypters, on the other hand, do not write anything to disk. As soon as the file is unencrypted and written to disk, it should be detected and quarantined by any decent modern antivirus. Scantime crypters generally evade detection from antivirus scanning until execution. Scantime crypters take an encrypted executable and reverse the encryption, and then write this executable to disk and execute it from there. ![]() Crypters may be divided into two categories: scantime and runtime. “Crypter” generally refers to software used by hackers and security researchers to conceal malware, particularly when infecting a victim’s computer. The below code is from this GitHub fork: Background Because the unencrypted binary executed from the stub.exe program never touches disk, it may be used to conceal programs from signature based detection systems employed by antivirus software. ![]() The second, stub.exe, takes this encrypted executable stored within itself as a resource, decrypts it and then executes it from memory. The first program, crypter.exe, is designed to obfuscate an executable file using a simple XOR encryption algorithm. The following project is separated into two separate components. The following is a very simple example of a crypter written in C++.
0 Comments
Leave a Reply. |