checkymander

Let's turn Any .NET Application into an LOL Bin

We can do this by experimenting with .config files.

Many defenders catch/detect files that are renamed, they do this by matching Original Filename to Process Name

In this example, we don't have to rename anything. We simple coerce a trusted signed app to load our Assembly.

We do this by directing the application to read a config file we provide.

checkymander

#!/bin/bash
for ip in $(seq 1 254); do
ping -c1 172.16.10.$ip |grep "bytes from " |cut -d" " -f 4|cut -d":" -f1 &
done

checkymander

#!/usr/bin/python
import os
for root, dirs, files, in os.walk(".", topdown=False):
  for name in files:
    print(os.path.join(root, name))	
  for name in dirs:
    print(os.path.join(root, name))

checkymander

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <!-- This inline task executes c# code. -->
  <!-- C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe SimpleTasks.csproj -->
  <!-- Save This File And Execute The Above Command -->
  <!-- Original Author: Casey Smith, Twitter: @subTee -->
  <!-- Modified by John Baek, @exploitpreacher to use ntqueueapcthread (https://github.com/FuzzySecurity/Sharp-Suite/tree/master/UrbanBishop) -->
  <!-- License: BSD 3-Clause -->
  <Target Name="Hello">
   <ClassExample />
  </Target>

checkymander

MS-MSDT 0-day Office RCE

MS Office docx files may contain external OLE Object references as HTML files. There is an HTML sceme "ms-msdt:" which invokes the msdt diagnostic tool, what is capable of executing arbitrary code (specified in parameters).

The result is a terrifying attack vector for getting RCE through opening malicious docx files (without using macros).

Here are the steps to build a Proof-of-Concept docx:

1. Open Word (used up-to-date 2019 Pro, 16.0.10386.20017), create a dummy document, insert an (OLE) object (as a Bitmap Image), save it in docx.

checkymander

/*!
 *
 * ROGUE
 *
 * GuidePoint Security LLC
 *
 * Threat and Attack Simulation
 * little tip: race condition at the RtlGetCtx so make a rop that sends an event if the rtl call finished
!*/

checkymander

// Copyright (C) 2022 Evan McBroom
// If you are using Visual Studio, you will need to disable the "Edit and Continue" feature.

// Prng based off of Parker Miller's
// "Multiplicative Linear Congruential Generator"
// https://en.wikipedia.org/wiki/Lehmer_random_number_generator
namespace mlcg {
    constexpr uint32_t modulus() {
        return 0x7fffffff;
    }

checkymander

16683189189467061193223884768707748125115707836338683708165636755281807331517563442745553664246724105870945763631169132260927526462734007835204880152893128450692630721572368535326118279180786621255867502609753166175114825563868872386555313011639026159359514256068100949221759953685226158201564474886176814194560402374867089196278252086615234757715302275261377043585010851175293923132633446346692061723922182900523634608569996664845671316859814804344017463762348282301284946271053184374916659024239637068041261659983151054361127497750752691523039603283781627522436175359723245473438312970933225984151370749165828689332628371556231892597912020228904274172
166831891894670611932238847687077481251157078363386837081656367552818073315175634427455536642467241058709457636311691322609275264627340078352048801528931284506926307215723685353261182791807866212558675026097531661751148255638688723865553130116390261593595142560681009492217599536852261582015644748861768141945604023748670891962782520866152347577153022752613770435850

checkymander

#ifndef PATCHLESS_AMSI_H
#define PATCHLESS_AMSI_H

#include <windows.h>

static const int AMSI_RESULT_CLEAN = 0;

PVOID g_amsiScanBufferPtr = nullptr;

unsigned long long setBits(unsigned long long dw, int lowBit, int bits, unsigned long long newValue) {

checkymander

using System;
using System.Runtime.InteropServices;


namespace API_Hashing
{
    class Program
    {
        [DllImport("kernel32", SetLastError = true, CharSet = CharSet.Ansi)]
        static extern IntPtr LoadLibrary([MarshalAs(UnmanagedType.LPStr)] string lpFileName);