Last active
October 22, 2021 23:58
-
-
Save hasherezade/2f09ae061b196ce16fce777472649346 to your computer and use it in GitHub Desktop.
Small utility do deobfuscate TrickBot strings
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
#include <stdio.h> | |
#include <windows.h> | |
#include "peconv.h" | |
/* | |
Requires a path to the original trick bot module: 0a7da84873f2a4fe0fcc58c88bbbe39d | |
*/ | |
#define OFFSET_DECODE_LIST 0x10ab0 //decode_from_the_list | |
#define OFFSET_DECODE_STR 0x10b30 // decode_string | |
#define OFFSET_ENC_LIST 0x1EC24 // enc_string_list (the list of obfuscated strings) | |
int (__cdecl *decode_from_the_list)(DWORD string_index, char *output_buf) = nullptr; | |
int (__cdecl *decode_str)(char* input_buf, char *output_buf) = nullptr; | |
int main(int argc, char *argv[]) | |
{ | |
if (argc < 2) { | |
std::cerr << "Args: <path to the malware> [string to decode]" << std::endl; | |
system("pause"); | |
return 0; | |
} | |
size_t v_size = 0; | |
char* mal_path = argv[1]; | |
char* inp_str = nullptr; | |
if (argc >= 3) { | |
inp_str = argv[2]; | |
} | |
std::cout << "Reading module from: " << mal_path << std::endl; | |
BYTE *malware = peconv::load_pe_executable(mal_path, v_size); | |
if (!malware) { | |
system("pause"); | |
return -1; | |
} | |
std::cout << "Loaded" << std::endl; | |
char** enc_list = (char**)((ULONGLONG)malware + OFFSET_ENC_LIST); | |
ULONGLONG func_offset = (ULONGLONG)malware + OFFSET_DECODE_LIST; | |
decode_from_the_list = (int (__cdecl *) (DWORD, char*)) func_offset; | |
func_offset = (ULONGLONG)malware + OFFSET_DECODE_STR; | |
decode_str = (int (__cdecl *) (char*, char*)) func_offset; | |
char out_buf[0x1000] = { 0 }; | |
if (inp_str != nullptr) { | |
DWORD res1 = decode_str(inp_str, out_buf); | |
if (res1 == 0) { | |
std::cerr << "[ERROR] Invalid input. Could not decode" << std::endl; | |
peconv::free_pe_buffer(malware, v_size); | |
return -1; | |
} | |
std::cout << out_buf << std::endl; | |
peconv::free_pe_buffer(malware, v_size); | |
system("pause"); | |
return 0; | |
} | |
//if nothing supplied, decode the internal table | |
for (DWORD i = 1; true; i++) { | |
if (!peconv::validate_ptr(malware, v_size, enc_list[i], sizeof(PVOID))) { | |
break; | |
} | |
DWORD res1 = decode_str(enc_list[i], out_buf); | |
if (res1 == 0) { | |
break; | |
} | |
std::cout << i << " : " << out_buf << std::endl; | |
} | |
peconv::free_pe_buffer(malware, v_size); | |
system("pause"); | |
return 0; | |
} | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
See details on the video: https://www.youtube.com/watch?v=KMcSAlS9zGE