Another shellcode injection technique using C++ that attempts to bypass Windows Defender using XOR encryption sorcery and UUID strings madness :).
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Firstly, generate a payload in binary format( using either
Havoc,CobaltStrikeormsfvenom) for instance, inmsfvenom, you can do it like so( the payload I'm using is for illustration purposes, you can use whatever payload you want ):msfvenom -p windows/messagebox -f raw -o shellcode.bin
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Then convert the shellcode( in binary/raw format ) into a
UUIDstring format using the Python3 script,bin_to_uuid.py:./bin_to_uuid.py -p shellcode.bin -o uuid.txt
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xorencrypt theUUIDstrings in theuuid.txtusing the Python3 script,xor_encryptor.py../xor_encryptor.py uuid.txt > xor_crypted_out.txt -
Copy the
C-stylearray in the file,xor_crypted_out.txt, and paste it in the C++ file as an array ofunsigned chari.e.unsigned char payload[]{your_output_from_xor_crypted_out.txt}
This shellcode injection technique comprises the following subsequent steps:
- First things first, it allocates virtual memory for payload execution and residence via
VirtualAlloc - It
xordecrypts the payload using thexorkey value - Uses
UuidFromStringAto convertUUIDstrings into their binary representation and store them in the previously allocated memory. This is used to avoid the usage of suspicious APIs likeWriteProcessMemoryormemcpy. - Uses
EnumCalendarInfoExto execute the payload previously loaded into memory( in step 1 )
- It doesn't use standard functions like
memcpyorWriteProcessMemorywhich are known to raise alarms to AVs/EDRs, this program uses the Windows API function calledUuidFromStringAwhich can be used to decode data as well as write it to memory( Isn't that great folks? And please don't say "NO!" :) ). - It uses the function call obfuscation trick to call the Windows API functions
- Lastly, because it looks unique :) ( Isn't it? :) )
- You have to change the
xorkey( line 13 ) to what you wish. This also has to be done in the./xor_encryptor.pypython3 script by changing theKEYvariable( line 5 ). The keys have to match! - You have to change the default
executable filenamevalue( line 15 ) to your filename. mingwwas used but you can use whichever compiler you prefer. :)
- Simply run this at your terminal/shell:
makeThe binary was scanned using antiscan.me on 01/08/2022.
https://research.nccgroup.com/2021/01/23/rift-analysing-a-lazarus-shellcode-execution-method/



